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Bartel Comp Materials

v1.0.12 ·Autonomous Materials Synthesis

Comprehensive knowledge pack covering Christopher Bartel's body of work in computational materials science — machine learning for materials discovery, autonomous synthesis laboratories, perovskite stability prediction, battery cathode design, solid-state synthesis thermodynamics, catalysis and energy conversion, and crystal topology characterization. Integrates 142 publications (2016-2026), 6 open-source code repositories from Bartel-Group GitHub, and cross-domain construct linkages spanning tolerance factors, neural network potentials, thermodynamic selectivity, and generative crystal models.

constructs
89
findings
283
propositions
0
sources
133
playbooks
5
// domain
Autonomous Materials Synthesis
Target inorganic materials for experimental synthesis
Synthesis reaction and experimental campaign 2021-2026
// top findings
283 empirical claims
view all →
F001 strong

GNN interatomic potentials (MACE-MP, CHGNet, SevenNet) achieve Discovery Acceleration Factors of 5–6x on the WBM test set, compared to ~1x for random baseline and ~2x for simpler one-shot GNN predictors like MEGNet.

F002 strong

Only 15.3% of WBM test structures are thermodynamically stable (on or within 0 meV/atom of the convex hull), establishing the random discovery baseline for computing DAF.

F003 strong

Models trained on geometry-relaxed structures significantly outperform those using unrelaxed (initial) structures for stability prediction, demonstrating that structural relaxation quality is a key bottleneck.

// abstract

Abstract

Domain: Autonomous Materials Synthesis

AI-driven autonomous experimentation platforms for accelerated materials synthesis. Covers the A-Lab robotic synthesis platform, ML-guided precursor selection, adaptive XRD characterization, Bayesian optimization of synthesis parameters, and closed-loop discovery workflows.

Temporal scope: 2021-2026 | Population: Target inorganic materials for experimental synthesis

Key Findings

  • GNN interatomic potentials (MACE-MP, CHGNet, SevenNet) achieve Discovery Acceleration Factors of 5–6x on the WBM test set, compared to ~1x for random baseline and ~2x for simpler one-shot GNN predictors like MEGNet. (positive, strong)
  • Only 15.3% of WBM test structures are thermodynamically stable (on or within 0 meV/atom of the convex hull), establishing the random discovery baseline for computing DAF. (null, strong)
  • Models trained on geometry-relaxed structures significantly outperform those using unrelaxed (initial) structures for stability prediction, demonstrating that structural relaxation quality is a key bottleneck. (positive, strong)
  • Graph neural network models (coGN, coNGN, MEGNet) systematically outperform composition-only models on structure-dependent properties like elastic moduli and phonon frequencies, while performing comparably on formation energy where composition is highly predictive. (positive, strong)
  • Gradient boosted trees with Magpie compositional features achieve competitive performance on formation energy prediction (MAE ~0.08 eV/atom) despite requiring no structural information, demonstrating the strength of composition-based features for chemically smooth properties. (positive, moderate)
  • CHGNet, trained on 1.5M MPtrj DFT trajectory frames with magnetic moment supervision, achieves force MAE of ~0.06 eV/Å and correctly predicts DFT-relaxed structure energies within ~0.03 eV/atom for the majority of Materials Project entries. (positive, strong)
  • GNN interatomic potentials (MACE-MP, CHGNet, SevenNet) achieve Discovery Acceleration Factors of 5–6x on the WBM test set, vs ~1x for random baseline and ~2x for simpler one-shot GNN predictors. (positive, strong)
  • Only 15.3% of WBM test structures are thermodynamically stable, establishing the random discovery baseline for computing DAF. (null, strong)

…and 275 more findings

// dependencies

Engines

  • engine.logistic_regression
  • engine.random_forest
  • engine.gradient_boosting
  • engine.ridge_regression
// tags
field
// registry meta
domainAutonomous Materials Synthesis
levelSynthesis reaction and experimental campaign
populationTarget inorganic materials for experimental synthesis
pax typefield
version1.0.12
published byPraxis Agent
archive80.3 KB
// key constructs
Vocabulary
// constructs.yaml
89 variables in the pax vocabulary
Each construct names a thing the field measures, with a kind and an authoritative definition.
C discovery_acceleration_factor
quantifiable
Discovery Acceleration Factor (DAF)
The ratio of a model's precision at top-k screening relative to random selection baseline. Quantifies how much faster a model identifies stable materials compared to untargeted DFT calculation. A DAF of 6 means 6x more discoveries per DFT calculation than random. Primary efficiency metric in Matbench Discovery.
C band_gap
quantifiable
Band Gap
The energy difference between the valence band maximum and conduction band minimum in a crystalline material, measured in eV via DFT (PBE functional). Determines whether a material is metallic (0 eV), semiconducting, or insulating. A key target in Matbench regression tasks.
C bulk_modulus
quantifiable
Bulk Modulus (VRH)
Voigt-Reuss-Hill averaged bulk modulus in GPa, measuring resistance to uniform compression. Computed from DFT elastic tensors. One of the Matbench benchmark regression targets (log_gvrh task).
C crystal_structure_representation
concept
Crystal Structure Representation
The mathematical encoding of a crystalline material for ML input. Ranges from composition-only vectors (element fractions) to graph-based representations (atoms as nodes, bonds as edges with distances/angles). Graph representations enable equivariant GNNs; compositional features enable tabular ML (CGCNN, MEGNet, MACE vs. Magpie, SOAP).
C gnn_interatomic_potential
process
Graph Neural Network Interatomic Potential (GNN-IP)
A machine-learned force field that maps crystal graph inputs to total energies, atomic forces, and stresses using message-passing neural networks. Trained on DFT trajectories (e.g., MPtrj ~1.6M structures), enabling geometry optimization at DFT accuracy but orders of magnitude faster. Examples: M3GNet, CHGNet, MACE-MP, SevenNet.
C mean_absolute_error_materials
quantifiable
Mean Absolute Error (MAE) for Property Prediction
Primary regression metric in Matbench: average absolute difference between predicted and DFT-computed material properties (eV/atom for energies, eV for band gaps, GPa for moduli). Lower is better; state-of-the-art models achieve ~0.02–0.05 eV/atom for formation energy.
C formation_energy_per_atom
quantifiable
Formation Energy per Atom
The energy released or required to form a crystal from its constituent elements in their standard reference states, normalized by the number of atoms. Measured in eV/atom via DFT calculations. The primary regression target in materials property prediction benchmarks.
C thermodynamic_stability
outcome
Thermodynamic Stability
Binary classification of whether a crystal is thermodynamically stable (on the convex hull) or not. In Matbench Discovery, 15.3% of WBM test structures are stable. The primary classification target for discovery benchmarks.
C revised_tolerance_factor
quantifiable
Revised Tolerance Factor (τ)
A geometric tolerance factor τ proposed by Bartel et al. (2019) that predicts whether a given ABX3 composition will form a stable perovskite structure. Unlike the classical Goldschmidt tolerance factor t, τ incorporates the oxidation state of A-site cation and uses a different functional form: τ = r_X/r_B - n_A(n_A - r_A/r_B / ln(r_A/r_B)). Achieves 92% accuracy on experimental perovskite/non-perovskite classification.
C energy_above_hull
quantifiable
Energy Above Convex Hull
The energy difference (eV/atom) between a material and the convex hull of thermodynamically stable phases at the same composition. E_hull = 0 means the material is on the hull (thermodynamically stable). Positive values indicate metastability. The primary metric for assessing whether a computationally predicted material could exist.
C neural_network_potential
process
Neural Network Interatomic Potential
A machine learning model trained on DFT data that predicts atomic energies, forces, and stresses from atomic positions and species. Examples include CHGNet, M3GNet, MACE, and SchNet. Enables molecular dynamics and structure relaxation at near-DFT accuracy but orders of magnitude faster. CHGNet uniquely incorporates magnetic moments and charge states.
C synthesis_success_rate
outcome
Synthesis Success Rate
The fraction of computationally predicted target materials that are successfully synthesized in the laboratory. In the A-Lab autonomous synthesis platform, measured as the number of targets where XRD confirms the desired phase divided by the total number of attempted syntheses. Key metric for evaluating the practical utility of computational materials discovery.
C thermodynamic_selectivity
quantifiable
Thermodynamic Selectivity
The ratio of thermodynamic driving force for the target synthesis product versus competing byproducts. Higher selectivity means the desired phase is strongly favored over alternative reaction products. Quantified as the free energy difference between the target reaction and the most favorable competing reaction pathway.
C perovskite_formability
outcome
Perovskite Formability
Binary classification of whether an ABX3 composition forms a perovskite crystal structure (1) or not (0). Determined experimentally via XRD phase identification. The primary prediction target for tolerance factor models and ML classifiers in the perovskite design literature.
C intercalation_voltage
quantifiable
Intercalation Voltage
The average voltage (V) at which a guest ion (Li+, Mg2+, Ca2+) intercalates into or de-intercalates from a cathode host structure. Computed from DFT total energies of the charged and discharged states. A key performance metric for battery cathode materials — higher voltage means higher energy density.
C force_field_mae
quantifiable
Force Prediction MAE
Mean absolute error (eV/Å) of an ML interatomic potential's predicted atomic forces compared to DFT reference calculations. The primary accuracy benchmark for neural network potentials. CHGNet achieves ~30 meV/Å on MPtrj test set; lower values indicate more accurate molecular dynamics trajectories.
C reaction_driving_force
quantifiable
Reaction Driving Force
The Gibbs free energy change (ΔG, kJ/mol or eV/atom) of a solid-state synthesis reaction at a given temperature. More negative values indicate stronger thermodynamic favorability. Used to rank candidate synthesis pathways and predict whether a target material can be made via a particular precursor combination.
C xrd_phase_identification_accuracy
quantifiable
XRD Phase Identification Accuracy
The accuracy of automated X-ray diffraction pattern matching for identifying crystalline phases in synthesized materials. In autonomous synthesis workflows, this is the classification accuracy of ML models that interpret XRD patterns to determine whether the target phase was successfully produced.
C oxygen_evolution_overpotential
quantifiable
Oxygen Evolution Overpotential
The excess potential (V) required above the thermodynamic minimum to drive the oxygen evolution reaction (OER) on a catalyst surface. Lower overpotential indicates a more active catalyst. Typically measured at 10 mA/cm² current density. A key metric for evaluating electrocatalysts for water splitting.
C persistent_homology_descriptor
process
Persistent Homology Descriptor
A topological data analysis method that characterizes the topology of electron density distributions in crystalline materials. Computes persistence diagrams from sublevel sets of the electron density field, capturing features like connected components, loops, and voids at multiple scales. Used to classify crystal structure types and predict material properties.
C goldschmidt_tolerance_factor
quantifiable
Goldschmidt Tolerance Factor (t)
The classical geometric tolerance factor t = (r_A + r_X) / sqrt(2)(r_B + r_X) proposed by Goldschmidt (1926) for predicting perovskite stability. Values near 1.0 favor cubic perovskite; t < 0.8 or t > 1.0 favor non-perovskite structures. Achieves ~74% accuracy, superseded by Bartel's revised tau.
C octahedral_factor
quantifiable
Octahedral Factor (μ)
The ratio of B-site cation radius to X-site anion radius (μ = r_B/r_X) in ABX3 perovskites. Values between 0.44 and 0.90 generally support stable octahedral coordination. Used alongside tolerance factors for perovskite stability prediction.
C perovskite_decomposition_energy
quantifiable
Perovskite Decomposition Energy
The DFT-calculated energy difference between a perovskite ABX3 compound and its most stable decomposition products (eV/atom). Negative values mean the perovskite is thermodynamically stable; positive values indicate it will spontaneously decompose. More physically rigorous than geometric tolerance factors.
C halide_perovskite_bandgap
quantifiable
Halide Perovskite Band Gap
The electronic band gap (eV) of halide perovskite materials (ABX3 where X = Cl, Br, I). Critical for optoelectronic applications — optimal solar cell performance requires band gaps of 1.1-1.7 eV. Tunable via composition engineering of A, B, and X sites.
C cation_disorder_energy
quantifiable
Cation Disorder Energy
The energy difference (eV/atom) between the fully ordered and disordered cation arrangements in a mixed-metal oxide. In rocksalt cathodes, partial cation disorder can enable percolating Li diffusion pathways while maintaining structural stability. Computed via special quasi-random structures (SQS) or cluster expansion.
C li_diffusion_barrier
quantifiable
Li Diffusion Barrier
The activation energy barrier (eV) for Li-ion migration between adjacent sites in a cathode crystal structure. Computed via nudged elastic band (NEB) calculations. Lower barriers enable faster charge/discharge rates. Typically 0.2-1.0 eV for intercalation cathodes.
C precursor_selection_score
quantifiable
Precursor Selection Score
A computed score ranking candidate precursor combinations for solid-state synthesis of a target material. Incorporates thermodynamic driving force, selectivity against competing products, and practical considerations (melting point, reactivity, commercial availability). Higher scores indicate more favorable precursor choices.
C synthesis_temperature
quantifiable
Synthesis Temperature
The temperature (°C or K) at which a solid-state synthesis reaction is conducted. Must be high enough for sufficient kinetics but low enough to avoid unwanted side reactions or decomposition. Typical range for ceramics: 600-1400°C. ML models increasingly predict optimal synthesis temperatures.
C metathesis_reaction_feasibility
outcome
Metathesis Reaction Feasibility
Binary assessment of whether a proposed metathesis (double exchange) reaction between two precursors will produce the desired product. Determined by comparing the thermodynamic driving force of the target reaction against all competing reaction pathways. A feasible metathesis reaction has negative ΔG and high selectivity.
C thermochemical_cycle_efficiency
quantifiable
Thermochemical Cycle Efficiency
The solar-to-fuel energy conversion efficiency (η) of a thermochemical water splitting cycle using metal oxide redox pairs. Depends on the reduction temperature, oxidation temperature, oxygen nonstoichiometry, and heat recovery. Typical values range from 5-40% depending on the oxide system and operating conditions.
C catalytic_loop_directionality
concept
Catalytic Loop Directionality
The directional control in programmable catalytic loops where dynamic oscillations in catalyst composition or surface state drive net reaction progress in a preferred direction. A key concept in catalytic resonance theory — the frequency and amplitude of oscillations determine whether the catalytic cycle runs forward, backward, or reaches a dynamic steady state.
C topological_fingerprint_similarity
quantifiable
Topological Fingerprint Similarity
A similarity metric between two crystalline materials based on the comparison of their persistent homology descriptors (persistence diagrams). Computed using Wasserstein or bottleneck distance between persistence diagrams derived from electron density fields. Enables structure-agnostic comparison of materials across different space groups.
C energy_prediction_mae
quantifiable
Energy Prediction MAE
Mean absolute error (meV/atom) of an ML model's predicted formation energy or total energy compared to DFT reference calculations. The primary accuracy benchmark for ML property prediction models. State-of-the-art models achieve ~20-30 meV/atom on Materials Project datasets.
C crystal_graph_representation
process
Crystal Graph Representation
A graph-based encoding of crystal structures where atoms are nodes and bonds are edges, with node/edge features encoding atomic properties and interatomic distances. Used as input to graph neural network models (CGCNN, MEGNet, SchNet, DimeNet) for property prediction. The choice of graph construction (cutoff radius, edge features) significantly affects model performance.
C double_perovskite_bandgap
quantifiable
Double Perovskite Band Gap
The electronic band gap of inorganic halide double perovskites (A2BB'X6), which determines their suitability for optoelectronic applications. Computed via hybrid DFT (HSE06) or GW-BSE methods.
C exciton_binding_energy
quantifiable
Exciton Binding Energy
The energy required to dissociate an electron-hole pair (exciton) in a semiconductor. In double perovskites, large exciton binding energies indicate strong electron-hole coupling, relevant for light-emitting applications.
C mg_migration_barrier
quantifiable
Mg-Ion Migration Barrier
The activation energy for Mg2+ ion hopping between sites in a host crystal structure, typically measured in meV. Lower barriers enable faster Mg-ion diffusion and better cathode rate capability in rechargeable Mg batteries.
C ca_intercalation_voltage
quantifiable
Ca Intercalation Voltage
The average electrochemical potential for reversible Ca2+ insertion/extraction in a host cathode material for Ca-ion batteries. Higher voltages enable higher energy density.
C mg_solid_electrolyte_conductivity
quantifiable
Mg Solid Electrolyte Conductivity
The ionic conductivity of solid-state Mg2+ conductors, critical for enabling all-solid-state Mg batteries. Limited by the high migration barriers of divalent Mg2+ ions in most crystalline hosts.
C spinel_cation_inversion
quantifiable
Spinel Cation Inversion
The degree to which cations in a spinel structure (AB2X4) occupy non-ideal crystallographic sites (tetrahedral vs octahedral), often expressed as inversion fraction. Affects Mg migration pathways and electrochemical properties.
C selectivity_metric
quantifiable
Selectivity Metric
A quantitative measure of how selectively a solid-state reaction produces the desired target phase versus competing byproduct phases, derived from thermodynamic reaction energies across all possible competing reactions in a chemical network.
C polymorph_selectivity
quantifiable
Polymorph Selectivity
The degree to which a solid-state synthesis pathway preferentially forms one crystal polymorph over thermodynamically competing polymorphs, governed by the interplay of reaction energy, surface energy, and nucleation barriers.
C thermodynamic_control_threshold
quantifiable
Thermodynamic Control Threshold
The minimum energy difference (in meV/atom) between the most favorable initial reaction product and competing phases above which product formation is reliably predicted by thermodynamics alone, empirically determined to be approximately 60 meV/atom.
C sequential_pairwise_mechanism
process
Sequential Pairwise Reaction Mechanism
The process by which solid-state ceramic synthesis proceeds through a sequence of binary reactions at precursor particle interfaces, where the most thermodynamically favorable pairwise reaction occurs first and intermediate phases progressively react to form the target product.
C short_range_order
quantifiable
Short-Range Order in Disordered Rocksalt
The local cation ordering in disordered rocksalt (DRX) cathode materials that deviates from a perfectly random distribution. SRO affects Li percolation networks, voltage profiles, and cycling stability in DRX cathodes.
C drx_fluorination_degree
quantifiable
DRX Fluorination Degree
The extent of fluorine incorporation into disordered rocksalt cathode materials, which modifies voltage, capacity, and Li percolation. Achieving target fluorination requires careful precursor selection to avoid LiF formation.
C dft_functional_accuracy
quantifiable
DFT Functional Accuracy for Solids
The accuracy of different density functional theory exchange-correlation approximations (PBE, SCAN, r2SCAN) for predicting thermodynamic properties of inorganic solids, including formation enthalpies and phase stability.
C ca_ion_diffusion_barrier
quantifiable
Ca-Ion Diffusion Barrier
The activation energy for Ca2+ migration in solid-state materials, critical for both Ca-ion battery cathodes and solid electrolytes. Ca2+ mobility is generally much lower than Li+ due to its larger size and higher charge density.
C nitride_perovskite_formability
quantifiable
Nitride Perovskite Formability
The likelihood that an ABN3 composition will crystallize in the perovskite structure. Nitride perovskites are extremely rare compared to oxide/halide analogs due to challenging synthesis and stability requirements.
C synthesis_condition_prediction
quantifiable
Synthesis Condition Prediction
ML-based prediction of optimal solid-state synthesis conditions (temperature, time, atmosphere) from precursor properties and reaction features, trained on text-mined literature data.
C ion_exchange_activation_energy
quantifiable
Ion Exchange Activation Energy
The energy barrier governing the rate of ion exchange reactions in solid-state synthesis, determined by defect formation energies and hopping barriers in the salt precursor rather than the ceramic target material.
C nasicon_stability_descriptor
quantifiable
NASICON Stability Descriptor
A two-dimensional descriptor combining cation size and electronegativity differences to predict the thermodynamic stability of NASICON-structured materials (NaxMM'(PO4)3). Enables rapid screening of the large NASICON composition space.
C anion_cometathesis
process
Anion Cometathesis
A double-ion exchange synthesis strategy where two anions are simultaneously exchanged between precursors, enabling formation of complex oxides at substantially lower temperatures than conventional ceramic routes by providing large thermodynamic driving forces.
C dft_prediction_accuracy
quantifiable
DFT Prediction Accuracy for Solid Stability
The accuracy with which density functional theory approximations (PBE, SCAN, r2SCAN) predict the thermodynamic stability of inorganic solids, measured as mean absolute error relative to experimental formation enthalpies.
C sulfide_cathode_voltage
quantifiable
Sulfide Cathode Voltage
The electrochemical voltage of sulfide-based cathode materials for Li-ion or multivalent batteries. Sulfide cathodes generally operate at lower voltages than oxides but may offer advantages in ionic conductivity and interface compatibility.
C gibbs_energy_descriptor
quantifiable
Gibbs Energy Descriptor
A physically motivated descriptor identified via SISSO (sure independence screening and sparsifying operator) that predicts the Gibbs free energy of inorganic crystalline solids as a function of temperature, enabling temperature-dependent phase stability calculations with ~50 meV/atom accuracy.
C decomposition_enthalpy
quantifiable
Decomposition Enthalpy
The enthalpy change associated with a compound decomposing into competing phases (other compounds and/or elemental forms). Unlike formation enthalpy which measures stability relative to elements only, decomposition enthalpy captures the true thermodynamic competition that determines compound stability.
C high_throughput_screening_yield
quantifiable
High-Throughput Screening Yield
The fraction of computationally screened candidate materials that pass stability and property filters and are ultimately validated experimentally, reflecting the efficiency of computational materials discovery pipelines.
C synthesis_prediction_calibration
quantifiable
Synthesis Prediction Calibration
The degree to which machine learning synthesizability scores align with ground-truth thermodynamic metrics (convex hull energies, selectivity scores), measuring whether ML models correctly estimate the likelihood that a hypothetical material can be experimentally synthesized.
C pairwise_reaction_energy
quantifiable
Pairwise Reaction Energy
The thermodynamic driving force for a reaction between a specific pair of solid precursors at their interface, used to predict which intermediate phases form first during solid-state synthesis of multicomponent ceramics.
C thermochemical_ammonia_yield
quantifiable
Thermochemical Ammonia Yield
The equilibrium yield of ammonia from solar thermochemical synthesis cycles involving metal nitride/oxide redox pairs, determined by Gibbs energy minimization across hydrolysis, reduction, nitrogen fixation, and nitride reformation steps.
C programmable_catalyst_enhancement
quantifiable
Programmable Catalyst Enhancement
The performance gain achieved by dynamically modulating catalyst surface binding energies through external forcing (voltage, strain, temperature oscillation), quantified as the ratio of dynamic to static catalytic rates or the reduction in required overpotential.
C catalytic_resonance_frequency
quantifiable
Catalytic Resonance Frequency
The optimal oscillation frequency at which forced dynamic modulation of a programmable catalyst achieves maximum rate enhancement, determined by the match between external forcing period and intrinsic catalytic turnover timescales.
C synthesis_temperature_prediction
quantifiable
Synthesis Temperature Prediction
ML prediction of optimal heating temperature for solid-state synthesis, learned from text-mined synthesis recipes. Correlated with precursor stability metrics (melting points, formation energies) following extended Tamman's rule.
C reaction_selectivity_metric
quantifiable
Reaction Selectivity Metric
Quantitative metrics (primary and secondary competition) assessing the favorability of target phase formation versus impurity phase formation in solid-state reactions. Used to rank and select synthesis reactions that maximize target yield.
C adaptive_measurement_efficiency
quantifiable
Adaptive Measurement Efficiency
The improvement in measurement effectiveness achieved by ML-guided adaptive experimentation compared to conventional static measurement protocols. For XRD, this means using early diffraction data to steer subsequent measurements toward informative angular ranges.
C metastable_polymorph_selectivity
process
Metastable Polymorph Selectivity
The ability to selectively synthesize a metastable crystal polymorph over the thermodynamically stable ground state through careful control of reaction energetics and surface energy contributions in solid-state synthesis.
C generative_crystal_model
concept
Generative Crystal Model
AI models (diffusion models, variational autoencoders, large language models) that generate novel crystal structures. Benchmarked against baseline methods like random charge-balanced prototype enumeration and data-driven ion exchange of known compounds.
C tolerance_factor_prediction
quantifiable
Tolerance Factor Prediction
ML-derived or analytically derived tolerance factors (e.g., tau) that predict the stability and formability of perovskite-structured compounds based on ionic radii, oxidation states, and electronegativity.
C synthesis_selectivity_metric
quantifiable
Synthesis Selectivity Metric
Quantitative measures (primary and secondary competition) of the thermodynamic favorability of target phase formation vs impurity phase formation in solid-state reactions. Higher selectivity indicates reactions that preferentially produce the desired product.
C proton_insertion_thermodynamics
quantifiable
Proton Insertion Thermodynamics
The thermodynamic energetics of proton (H+) incorporation into perovskite and brownmillerite oxide structures, relevant for protonic ceramic fuel cells and electrochemical applications.
C cation_vacancy_water_splitting
process
Cation Vacancy-Mediated Water Splitting
A mechanism for thermochemical water splitting where cation vacancies in spinel metal oxides (rather than conventional oxygen vacancies) mediate the redox cycling, enabled by cation site inversion that lowers vacancy formation energies.
C betti_curve_descriptor
quantifiable
Betti Curve Descriptor
A topological descriptor derived from persistent homology applied to electron density fields of crystalline solids, encoding bonding characteristics by tracking topological features (connected components, loops, voids) across varying density thresholds as a function of filtration parameter.
C text_mined_synthesis_database
concept
Text-Mined Synthesis Database
A structured dataset of synthesis procedures extracted from scientific literature using NLP and text mining, containing precursors, conditions, and outcomes that enable data-driven analysis of synthesis-structure-property relationships.
C topological_descriptor
quantifiable
Topological Descriptor (Betti Curves)
Descriptors derived from persistent homology (Betti curves) that compress electron density distributions into compact representations capturing bonding characteristics through components, cycles, and voids across electron density thresholds.
C mlip_surface_prediction
process
MLIP Surface Prediction
Application of machine learning interatomic potentials (MLIPs) to compute surface phase diagrams, surface energies, and surface reconstructions at a fraction of the DFT cost while maintaining near-DFT accuracy.
C metathesis_driving_force
quantifiable
Metathesis Driving Force
The thermodynamic driving force available in metathesis (double displacement) reactions for inorganic synthesis, which can dramatically alter the reaction landscape to enable rapid and selective formation of target phases that are otherwise difficult to synthesize via traditional routes.
C automated_phase_identification
process
Automated Phase Identification
ML-based methods for automatically identifying crystalline phases from X-ray diffraction data, including probabilistic neural networks and adaptive measurement strategies that optimize data collection for phase detection.
C ml_formation_energy_model
quantifiable
ML Formation Energy Model
Machine learning models trained to predict formation energies of inorganic crystalline solids from compositional and structural features. Model accuracy depends critically on training data quality, diversity, and balance across chemical space.
C pairwise_reaction_model
concept
Pairwise Reaction Model
A model for solid-state synthesis where phase evolution from multiple precursors proceeds as a sequence of interfacial reactions initiating between two phases at a time. The most reactive pairwise interface determines which non-equilibrium intermediate phases form.
C post_generation_screening
process
Post-Generation Screening Efficiency
The improvement in success rates achieved by passing ML-generated candidate materials through stability and property filters from pre-trained models (e.g., universal interatomic potentials) as a low-cost post-processing step.
C topological_electron_density_descriptor
quantifiable
Topological Electron Density Descriptor
Betti curve descriptors derived from persistent homology that compress electron densities of crystalline materials into compact representations, capturing bonding characteristics by encoding topological features (components, cycles, voids).
C nasicon_tolerance_factor
quantifiable
NASICON Tolerance Factor
Machine-learned tolerance factor for NASICON-structured materials based on Na content, elemental radii, electronegativities, and Madelung energy. Classifies NASICON phases in terms of their synthetic accessibility.
C charge_informed_mlip
concept
Charge-Informed MLIP
Machine learning interatomic potentials that incorporate charge/oxidation state information (e.g., via magnetic moment prediction) to describe both atomic and electronic degrees of freedom, enabling modeling of redox-coupled phenomena in electrochemical systems.
C ml_dft_error_correction
process
ML DFT Error Correction
Use of machine learning models to correct systematic errors in DFT-computed enthalpies of formation by learning error patterns from electronic structure features. Can reduce PBE errors from MAE ~195 meV/atom to ~80 meV/atom.
C text_mined_synthesis_data
concept
Text-Mined Synthesis Data
Structured synthesis datasets extracted from scientific literature using NLP/text mining methods. These datasets capture synthesis procedures, precursors, conditions (temperature, time, atmosphere), and outcomes for thousands of inorganic materials, enabling data-driven synthesis prediction.
C cathode_capacity
quantifiable
Cathode Specific Capacity
The gravimetric charge storage capacity of a battery cathode material (mAh/g). Determined by the number of intercalatable ions per formula unit and the molecular weight. Higher capacity enables higher energy density batteries. Theoretical capacity from DFT; practical capacity from electrochemical cycling.
C chalcogenide_perovskite_stability
quantifiable
Chalcogenide Perovskite Stability
The thermodynamic stability of perovskites with chalcogenide anions (S2-, Se2-, Te2-) instead of oxide or halide anions. These materials are scarce despite favorable tolerance factors, suggesting additional instability mechanisms.
C chemical_looping_material_viability
quantifiable
Chemical Looping Material Viability
The thermodynamic feasibility of a redox-active material to mediate chemical looping processes, assessed through equilibrium analysis of oxidation and reduction half-cycles under process-relevant conditions.
// findings.yaml
283 empirical claims
Each finding cites a source and reports effect size, standard error, p-value, and sample size where available.
F002 strong

Only 15.3% of WBM test structures are thermodynamically stable (on or within 0 meV/atom of the convex hull), establishing the random discovery baseline for computing DAF.

// method: DFT convex hull analysis of WBM dataset (256,963 materials)
F005 moderate

Gradient boosted trees with Magpie compositional features achieve competitive performance on formation energy prediction (MAE ~0.08 eV/atom) despite requiring no structural information, demonstrating the strength of composition-based features for chemically smooth properties.

// method: Matbench cross-validation, gradient boosting with Magpie featurization
F006 strong

CHGNet, trained on 1.5M MPtrj DFT trajectory frames with magnetic moment supervision, achieves force MAE of ~0.06 eV/Å and correctly predicts DFT-relaxed structure energies within ~0.03 eV/atom for the majority of Materials Project entries.

// method: held-out test set evaluation on Materials Project data; phonon benchmark
F008 strong

Only 15.3% of WBM test structures are thermodynamically stable, establishing the random discovery baseline for computing DAF.

// method: DFT convex hull analysis of WBM dataset (256,963 materials)
F012 strong

The revised tolerance factor τ achieves 92% classification accuracy for perovskite vs non-perovskite ABX3 compositions across 576 experimental data points, significantly outperforming the classical Goldschmidt tolerance factor t (74% accuracy).

// effect: AUC improvement from 0.74 to 0.92
// method: logistic_regression
F013 strong

The revised tolerance factor τ correctly predicts the stability of both oxide and halide perovskites within a single model, whereas previous tolerance factors required separate parameterizations for different anion chemistries.

// method: logistic_regression
F014 strong

The A-Lab autonomous synthesis platform successfully synthesized 41 of 58 target materials (71% success rate) within 17 days of continuous operation, with each synthesis attempt taking approximately 4 hours from precursor mixing to XRD characterization.

// effect: 71% success rate (41/58 targets)
// method: experimental_validation
F015 strong

ML-guided precursor selection combined with Bayesian optimization of synthesis parameters enabled the A-Lab to autonomously discover synthesis recipes for materials that had never been experimentally reported before.

// method: bayesian_optimization
F016 strong

CHGNet achieves force prediction MAE of 30 meV/Å and energy MAE of 22 meV/atom on the Materials Project trajectory (MPtrj) dataset containing 1.58M structures, while uniquely modeling charge states and magnetic moments through explicit charge equilibration.

// effect: Force MAE: 30 meV/Å; Energy MAE: 22 meV/atom
// method: graph_neural_network
F017 strong

CHGNet correctly predicts the magnetic ground states of Fe, Co, Ni, and Mn-containing materials and the charge-transfer-driven phase transitions in LixMnO2 battery cathodes, capabilities absent in charge-agnostic potentials like M3GNet.

// method: molecular_dynamics
F019 moderate

The primary bottleneck in autonomous materials discovery is not computational prediction accuracy but the gap between thermodynamic stability predictions and practical synthesizability — many thermodynamically stable materials remain experimentally inaccessible.

// method: review_synthesis
F020 strong

Of 903 Cs2BB'Cl6 double perovskite compositions screened using the revised tolerance factor tau, 311 were predicted as likely perovskites and 261 of those (84%) were predicted thermodynamically synthesizable with decomposition enthalpy below 0.05 eV/atom.

// effect: 261/311 = 84% synthesizability rate among tau-predicted perovskites
// method: DFT (PBE+U) + tolerance factor screening
F021 strong

47 non-toxic Cs2BB'Cl6 double perovskites were identified with direct or nearly direct band gaps between 1-3 eV suitable for optoelectronic applications, computed with HSE06 hybrid functional.

// effect: 47 candidates with 1-3 eV direct band gaps from 261 stable compounds
// method: HSE06 hybrid DFT
F022 strong

Triple-alkali double perovskites Cs2[Alk]+[TM]3+Cl6 exhibit large and tunable exciton binding energies due to mixing of Alk-Cl and TM-Cl sublattices, enabling small band gaps with strong electron-hole coupling as computed by GW-BSE.

// effect: Large exciton binding energies from sublattice mixing mechanism
// method: GW-BSE (Bethe-Salpeter equation)
F023 strong

Decomposition enthalpies (Delta_Hd) provide more accurate stability predictions than formation enthalpies (Delta_Hf) because DFT systematic errors partially cancel when comparing chemically similar phases. The phase stability of 71 ternary compounds showed much better agreement with experiment when assessed via decomposition reactions.

// effect: Systematic DFT errors cancel in decomposition reactions vs formation energies
// method: DFT (PBE, SCAN) with experimental comparison
F024 strong

For 71 ternary compounds, DFT-predicted phase stability (stable vs unstable) agreed with experiment in the majority of cases when decomposition reactions to competing phases were used, but formation enthalpy from elements showed larger systematic errors that did not cancel.

// effect: Error cancellation in decomposition enthalpies improves stability prediction accuracy
// method: DFT benchmark against 71 experimental ternary compounds
F025 foundational

A comprehensive review establishes that computational approaches for thermodynamic stability prediction of inorganic solids fall into three categories: (1) DFT-based convex hull analysis, (2) machine learning of formation energies, and (3) descriptor-based approaches like tolerance factors. Each has distinct accuracy-throughput tradeoffs.

// method: Literature review
F026 strong

Chalcogenide perovskites (ABX3, X=S,Se,Te) are thermodynamically unstable despite having favorable tolerance factors, indicating that tolerance factor alone is insufficient to predict formability for chalcogenide anions. The instability has both thermodynamic and chemical origins.

// effect: Favorable tau but thermodynamically unstable - tolerance factor necessary but not sufficient
// method: DFT first-principles calculations
F028 strong

High-throughput DFT screening followed by experimental synthesis successfully realized two new Ce-based nitride perovskites, CeMoN3 and CeWN3, adding to the very small number of experimentally known nitride perovskites.

// effect: 2 new nitride perovskites experimentally realized from computational predictions
// method: High-throughput DFT screening + experimental synthesis
F029 strong

Nitride perovskites remain extremely rare experimentally despite the broad diversity of oxide and halide perovskites, with CeMoN3 and CeWN3 joining only a handful of previously known ABN3 compounds.

// effect: Only ~5 nitride perovskites known experimentally before this work
// method: Experimental synthesis with DFT guidance
F030 strong

A simple 2D descriptor based on cation size and electronegativity differences, extracted via sure independence screening and ML ranking, classifies NASICON phase stability with high accuracy across the full composition space.

// effect: 2D descriptor sufficient for NASICON stability classification
// method: Sure independence screening + ML ranking
F031 strong

MgCrMnO4 spinel with 18% Mg/Mn inversion was synthesized and studied as a high-voltage Mg cathode. Operando XRD enabled accurate quantification of cation migration during cycling, revealing the Mg-ion migration mechanism through spinel lattice sites.

// effect: 18% Mg/Mn inversion; first accurate operando quantification of cation contents in multivalent battery spinel
// method: Operando synchrotron XRD with Rietveld refinement
F032 strong

First demonstration of high-quality operando diffraction data enabling accurate quantification of cation contents in crystallographic sites during multivalent battery cycling, establishing a new methodology for studying Mg-ion migration mechanisms.

// method: Operando synchrotron XRD
F033 moderate

MgxCr2S4 spinel cathode operates via the high-voltage Cr3+/4+ redox couple. DFT predicted it as a suitable high-voltage Mg cathode, but experimental electrochemical cycling showed limited reversibility, with voltage plateaus observed but capacity fading over cycles.

// effect: Cr3+/4+ redox enables higher voltage than Mo6S8 or Ti2S4 sulfide cathodes, but limited cycling stability
// method: DFT prediction + experimental electrochemistry
F034 moderate

Existing sulfide cathodes for Mg batteries (MgxMo6S8, MgxTi2S4) have voltages too low for high energy density cells. The Cr3+/4+ couple in MgxCr2S4 was predicted computationally to provide significantly higher voltage.

// effect: Cr3+/4+ voltage significantly higher than existing sulfide cathodes
// method: DFT voltage calculation
F035 strong

Seven MgLn2X4 (Ln=lanthanoid, X=S,Se) chalcogenide spinels are calculated to have low Mg migration barriers (<380 meV) and are thermodynamically stable or nearly stable (within 50 meV/atom of hull). Larger Ln cations increase Mg mobility but decrease spinel structure stability.

// effect: Migration barriers <380 meV; stability within 50 meV/atom; mobility-stability tradeoff with Ln size
// method: DFT-NEB migration barrier calculations
F036 strong

As the size of the lanthanoid cation increases in MgLn2X4 spinels, Mg mobility increases but thermodynamic stability in the spinel structure decreases, revealing a fundamental tradeoff between conductivity and structural stability for Mg solid electrolytes.

// effect: Inverse relationship between Ln size, Mg mobility, and spinel stability
// method: DFT-NEB across lanthanoid series
F037 strong

First-principles evaluation of P-type layered CaTM2O4 (TM=Ti,V,Cr,Mn,Fe,Co,Ni) demonstrates that several compositions have excellent battery properties: thermodynamic stability, average voltages of 2.2-4.2 V vs Ca/Ca2+, energy densities up to 600-800 Wh/kg, synthesizability, and reasonable Ca-ion mobility.

// effect: Voltages 2.2-4.2 V; energy densities 600-800 Wh/kg for best TM compositions
// method: DFT (GGA+U) systematic evaluation
F038 strong

P-type layered Ca transition metal oxides represent a promising class of Ca cathode materials, with Ca-V and Ca-Cr compositions showing the best combination of high voltage, stability, and ion mobility among the TM series evaluated.

// effect: Ca-V, Ca-Cr best overall performance in TM series
// method: DFT NEB + thermodynamic analysis
F039 strong

Nanocrystalline layered MnOx with high defect concentration and lattice water demonstrates remarkable room-temperature Ca2+ electrochemical activity, achieving capacity of ~100-130 mAh/g. Atomic defects and lattice water are critical enablers of Ca2+ mobility in the oxide framework.

// effect: ~100-130 mAh/g capacity for Ca2+ intercalation at room temperature in defective MnOx
// method: Experimental electrochemistry + XRD characterization
F040 strong

Slow Ca2+ kinetics in oxide electrodes is the primary bottleneck for Ca-ion batteries. High defect concentrations and structural water in nanocrystalline MnOx overcome this kinetic limitation, enabling room-temperature Ca intercalation that is not possible in well-ordered oxides.

// effect: Defective nanocrystals enable RT Ca2+ intercalation vs no activity in ordered phases
// method: Electrochemistry + structural characterization
F041 strong

Thermodynamic selectivity metrics derived from first-principles reaction energies across a 82,985-reaction chemical network successfully predict which synthesis routes for BaTiO3 yield the target phase with fewest impurities, as confirmed by synchrotron diffraction of 9 tested routes.

// effect: 3,520 reactions analyzed; 82,985-reaction network; 9 synthesis routes experimentally validated
// method: DFT thermodynamic calculations, synchrotron X-ray diffraction
F042 strong

Unconventional precursor combinations identified through selectivity analysis produce BaTiO3 faster with fewer impurities than the conventional BaCO3+TiO2 route, demonstrating that complex chemistries in precursor selection substantially impact synthesis outcomes.

// method: Computational screening followed by experimental validation
F043 strong

Metathesis reactions enable rapid and selective synthesis of MgCr2S4 thiospinel by engineering large thermodynamic driving forces through salt byproduct formation, bypassing the laborious traditional ceramic synthesis route.

// effect: 42 citations; selective formation of target phase confirmed by XRD
// method: Metathesis reaction design with DFT-computed driving forces
F044 strong

Precursor selection controls polymorph selectivity in solid-state synthesis by tuning reaction energy, which modulates critical nucleus size and surface energy contributions. For LiTiOPO4, different precursor sets selectively form different polymorphs via this mechanism.

// method: In situ characterization, DFT, nucleation theory
F045 moderate

Surface energy plays a critical role in promoting nucleation of metastable phases during solid-state synthesis. When reaction energies are large, the metastable polymorph with lower surface energy can nucleate preferentially despite being higher in bulk free energy.

F046 strong

A threshold of >=60 meV/atom energy difference between the most favorable initial product and competing phases defines the regime of thermodynamic control in solid-state reactions. Below this threshold, kinetic factors dominate product selection.

// effect: >=60 meV/atom threshold; 37 reactant pairs characterized in situ
// method: In situ synchrotron characterization of 37 reactant pairs
F047 strong

Only 15% of possible solid-state reactions in the Materials Project database fall within the thermodynamic control regime where initial product formation can be predicted from first principles alone.

// effect: 15% of reactions under thermodynamic control; Materials Project database analysis
// method: Computational analysis of Materials Project reaction database
F048 strong

YBCO ceramic synthesis proceeds through sequential pairwise reactions at precursor interfaces. Substituting BaCO3 with BaO2 redirects the pathway through a low-temperature eutectic melt, reducing synthesis time from 12+ hours to 30 minutes (24x speedup).

// effect: 24x synthesis time reduction (12+ hours to 30 minutes)
// method: In situ XRD, electron microscopy, computational thermodynamics
F049 strong

Computational thermodynamics successfully identifies the most reactive precursor pair interfaces in heterogeneous powder mixtures, predicting the sequence of intermediate phase formation during ceramic synthesis.

// method: Computational thermodynamics validated by in situ XRD
F050 strong

Pair distribution function (PDF) analysis combined with cluster-expansion-based structural models accurately captures short-range cation ordering in disordered rocksalt cathodes. The approach was validated on neutron scattering data for Li-Mn-O-F DRX compositions.

// effect: First-principles SRO models match experimental PDF data quantitatively
// method: Neutron PDF + cluster expansion modeling
// propositions.yaml
0 theoretical claims
Propositions are the field's reusable rules of thumb — they span findings without being tied to a single study.
// no propositions
This pax does not declare propositions. Propositions capture theoretical claims linking constructs.
// sources.yaml
133 citations
The evidentiary backing — papers, datasets, reports — every finding can be traced to one of these.
S001
Bartel, C.J. (2021). Toward autonomous design and synthesis of novel inorganic materials.
S002
Riebesell, J., Goodall, R.E.A., Jain, A., Benner, P., Persson, K.A., Lee, A.A. (2025). A framework to evaluate machine learning crystal stability predictions.
S003
Dunn, A., Wang, Q., Ganose, A., Dopp, D., Jain, A. (2020). Benchmarking materials property prediction methods: the Matbench test set and Automatminer reference algorithm.
S004
Deng, B., Zhong, P., Jun, K., Riebesell, J., Han, K., Bartel, C.J., Ceder, G. (2023). CHGNet as a pretrained universal neural network potential for charge-informed atomistic modelling.
S005
Bartel, C.J.; Sutton, C.; Goldsmith, B.R.; Ouyang, R.; Musgrave, C.B.; Ghiringhelli, L.M.; Scheffler, M. (2019). New tolerance factor to predict the stability of perovskite oxides and halides.
S006
Szymanski, N.J.; Rendy, B.; Fei, Y.; Kumar, R.E.; He, T.; Milber, D.; Jiang, H.; Bartel, C.J.; et al. (2023). An autonomous laboratory for the accelerated synthesis of novel materials.
S007
Christopher J. Bartel, Jacob M. Clary, Christopher Sutton, Connor W. Scanlon, Benjamin M. Goldsmith, Muratahan Aykol, Gerbrand Ceder, Stephan Lany (2020). Inorganic Halide Double Perovskites with Optoelectronic Properties Modulated by Sublattice Mixing.
S008
Christopher J. Bartel, Alan W. Weimer, Stephan Lany, Charles B. Musgrave, Aaron M. Holder (2018). The role of decomposition reactions in assessing first-principles predictions of solid stability.
S009
Christopher J. Bartel (2022). Review of computational approaches to predict the thermodynamic stability of inorganic solids.
S010
Andrew Carr, Talia Glinberg, Nathan Stull, Christopher J. Bartel (2025). Origins of chalcogenide perovskite instability.
S011
Rachel Sherbondy, Rebecca W. Smaha, Christopher J. Bartel, Michael C. Brennan, Bethany E. Matthews, Stephan Lany, Andriy Zakutayev (2022). High-Throughput Selection and Experimental Realization of Two New Ce-Based Nitride Perovskites: CeMoN3 and CeWN3.
S012
Liang Yin, Bob Jin Kwon, Yunyeong Choi, Alyssa Bartel, Hakim Iddir, Baris Key, Sang-Don Han, Christopher J. Bartel, Gerbrand Ceder, Jordi Cabana, Brian J. Ingram (2021). Operando X-ray Diffraction Studies of the Mg-Ion Migration Mechanisms in Spinel Cathodes for Rechargeable Mg-Ion Batteries.
S013
Lauren Blanc, Christopher J. Bartel, Haegyeom Kim, Liang Yin, Bob Jin Kwon, Baris Key, Timothy T. Fister, Brian J. Ingram, Gerbrand Ceder (2021). Toward the Development of a High-Voltage Mg Cathode Using a Chromium Sulfide Host.
S014
Julius Koettgen, Christopher J. Bartel, Gerbrand Ceder (2020). Computational investigation of chalcogenide spinel conductors for all-solid-state Mg batteries.
S015
Haesun Park, Christopher J. Bartel, Gerbrand Ceder (2021). Layered Transition Metal Oxides as Ca Intercalation Cathodes: A Systematic First-Principles Evaluation.
S016
Bob Jin Kwon, Liang Yin, Christopher J. Bartel, Gerbrand Ceder, Brian J. Ingram, Jordi Cabana (2022). Intercalation of Ca into a Highly Defective Manganese Oxide at Room Temperature.
S017
McDermott, McBride, Regier, Tran, Chen, Corrao, Gallant, Kamm, Bartel, Chapman, Khalifah, Ceder, Neilson, Persson (2023). Assessing Thermodynamic Selectivity of Solid-State Reactions for the Predictive Synthesis of Inorganic Materials.
S018
Miura, Ito, Bartel, Sun, Rosero-Navarro, Tadanaga, Nakata, Maeda, Ceder (2020). Selective metathesis synthesis of MgCr2S4 by control of thermodynamic driving forces.
S019
Zeng, Szymanski, He, Jun, Gallington, Huo, Bartel, Ouyang, Ceder (2024). Selective formation of metastable polymorphs in solid-state synthesis.
S020
Szymanski, Byeon, Sun, Zeng, Bai, Kunz, Kim, Helms, Bartel, Kim, Ceder (2024). Quantifying the regime of thermodynamic control for solid-state reactions during ternary metal oxide synthesis.
S021
Miura, Bartel, Goto, Mizuguchi, Moriyoshi, Kuroiwa, Wang, Yaguchi, Shirai, Nagao, Rosero-Navarro, Tadanaga, Ceder, Sun (2021). Observing and Modeling the Sequential Pairwise Reactions that Drive Solid-State Ceramic Synthesis.
S022
Nathan J. Szymanski, Zhengyan Lun, Jue Liu, Gerbrand Ceder (2023). Modeling Short-Range Order in Disordered Rocksalt Cathodes by Pair Distribution Function Analysis.
S023
Nathan J. Szymanski, Yan Zeng, Tyler H. Bennett, Shuo Bai, Christopher J. Bartel, Gerbrand Ceder (2022). Understanding the Fluorination of Disordered Rocksalt Cathodes through Rational Exploration of Synthesis Pathways.
S024
Manish Kothakonda, Aaron D. Kaplan, Eric B. Isaacs, Christopher J. Bartel, James W. Furness, Jianwei Sun, John P. Perdew, Adrienn Ruzsinszky (2022). Testing the r2SCAN Density Functional for the Thermodynamic Stability of Solids with and without a van der Waals Correction.
S025
Ryan Kingsbury, Ayush Gupta, Christopher J. Bartel, Jason M. Munro, Shyam Dwaraknath, Matthew Horton, Kristin A. Persson (2022). Performance comparison of r2SCAN and SCAN metaGGA density functionals for solid materials via an automated, high-throughput computational workflow.
S026
Yu Chen, Christopher J. Bartel, Maxim Avdeev, Gerbrand Ceder (2021). Solid-State Calcium-Ion Diffusion in Ca1.5Ba0.5Si5O3N6.
S027
Huo, Bartel, He, Trewartha, Dunn, Ouyang, Jain, Ceder (2022). Machine-Learning Rationalization and Prediction of Solid-State Synthesis Conditions.
S028
He, Huo, Bartel, Wang, Cruse, Ceder (2023). Precursor recommendation for inorganic synthesis by machine learning materials similarity from scientific literature.
S029
Szymanski, Nevatia, Bartel, Zeng, Ceder (2023). Autonomous and dynamic precursor selection for solid-state materials synthesis.
S030
Rognerud, Rom, Todd, Singstock, Bartel, Holder, Neilson (2019). Kinetically Controlled Low-Temperature Solid-State Metathesis of Manganese Nitride Mn3N2.
S031
Cosby, Bartel, Corrao, Yakovenko, Gallington, Ceder, Khalifah (2023). Thermodynamic and Kinetic Barriers Limiting Solid-State Reactions Resolved through In Situ Synchrotron Studies of Lithium Halide Salts.
S032
Lauren Blanc, Yunyeong Choi, Abhinandan Shyamsunder, Christopher J. Bartel, Bob Jin Kwon, Gerbrand Ceder, Brian J. Ingram, Linda F. Nazar (2022). Phase Stability and Kinetics of Topotactic Dual Ca2+-Na+ Ion Electrochemistry in NaSICON NaV2(PO4)3.
S033
Julius Koettgen, Christopher J. Bartel, Jimmy-Xuan Shen, Gerbrand Ceder (2020). First-principles study of CaB12H12 as a potential solid-state conductor for Ca.
S034
Nathan J. Szymanski, Christopher J. Bartel (2024). Computationally Guided Synthesis of Battery Materials.
S035
Bin Ouyang, Jingyang Wang, Tanjin He, Christopher J. Bartel, Haoyan Huo, Tiago Botari, Kristin A. Persson, Gerbrand Ceder (2021). Synthetic accessibility and stability rules of NASICONs.
S036
Tran, Wustrow, O'Nolan, Tao, Bartel, He, McDermott, McBride, Chapman, Billinge, Persson, Ceder, Neilson (2023). Selective Synthesis of Defect-Rich LaMnO3 by Low-Temperature Anion Cometathesis.
S037
Szymanski, Zeng, Bennett, Patil, Keum, Self, Bai, Cai, Giovine, Ouyang, Wang, Bartel, Clement, Tong, Nanda, Ceder (2022). Understanding the Fluorination of Disordered Rocksalt Cathodes through Rational Exploration of Synthesis Pathways.
S038
Christopher J. Bartel (2021). Data-centric approach to improve machine learning models for inorganic materials.
S039
Santosh Adhikari, Christopher J. Bartel, Christopher Sutton (2023). Interpretable machine learning to understand the performance of semilocal density functionals for materials thermochemistry.
S040
Wenhao Sun, Christopher J. Bartel, Elisabetta Arca, Sage R. Bauers, Bethany Matthews, Bernardo Orvananos, Bryan R. Goldsmith, Tiago Botari, Aaron M. Holder, Stephan Lany, Andriy Zakutayev, Vladan Stevanovic, Aaron M. Holder (2019). A map of the inorganic ternary metal nitrides.
S041
Akira Miura, Hiroaki Ito, Christopher J. Bartel, Wenhao Sun, Naoto Rosero-Navarro, Kiyoharu Tadanaga, Hideo Nakata, Kazuhiko Maeda, Gerbrand Ceder (2020). Selective metathesis synthesis of MgCr2S4 by control of thermodynamic driving forces.
S042
Yi-Ting Cheng, Yuta Fujii, Yu Nomata, Christopher J. Bartel (2024). Synthesis, Electronic Structure, and Redox Chemistry of Li2MnP2S6, a Candidate High-Voltage Cathode Material.
S043
Bartel CJ, Trewartha A, Wang Q, Dunn A, Jain A, Ceder G (2019). A map of the inorganic ternary metal nitrides.
S044
Bartel CJ (2022). Review of computational approaches to predict the thermodynamic stability of inorganic solids.
S045
Bartel CJ, Millican SL, Deml AM, Rumptz JR, Tumas W, Weimer AW, Lany S, Musgrave CB, Holder AM (2019). Physical descriptor for the Gibbs energy of inorganic crystalline solids and temperature-dependent materials chemistry.
S046
Justin C. Hancock, Kent J. Griffith, Yunyeong Choi, Christopher J. Bartel, Gerbrand Ceder (2021). Expanding the Ambient-Pressure Phase Space of CaFe2O4-Type Sodium Postspinel Host-Guest Compounds.
S047
Ouyang, Wang, He, Bartel, Huo, Wang, Lacivita, Kim, Ceder (2021). Synthetic accessibility and stability rules of NASICONs.
S048
Bartel (2022). Review of computational approaches to predict the thermodynamic stability of inorganic solids.
S049
Goldsmith BR, Esterhuizen J, Liu JX, Bartel CJ, Sutton C (2018). Machine learning for heterogeneous catalyst design and discovery.
S050
Murphy, Gathmann, Bartel, Abdelrahman, Dauenhauer (2024). Catalytic resonance theory: Circumfluence of programmable catalytic loops.
S051
Murphy, Noordhoek, Gathmann, Dauenhauer, Bartel (2024). Catalytic resonance theory: forecasting the flow of programmable catalytic loops.
S052
Lee JW, Park WB, Lee JH, Singh SP, Sohn KS (2021). Probabilistic Deep Learning Approach to Automate the Interpretation of Multi-phase Diffraction Spectra.
S053
Nathan J. Szymanski, Christopher J. Bartel (2025). Establishing baselines for generative discovery of inorganic crystals.
S054
Goldsmith, Esterhuizen, Liu, Bartel, Sutton (2018). Machine learning for heterogeneous catalyst design and discovery.
S055
Cruse, Baibakova, Abdelsamie, Hong, Bartel, Trewartha, Jain, Sutter-Fella, Ceder (2023). Text Mining the Literature to Inform Experiments and Rationalize Impurity Phase Formation for BiFeO3.
S056
Bartel CJ, Weimer AW, Lany S, Musgrave CB, Holder AM (2022). Testing the r2SCAN Density Functional for the Thermodynamic Stability of Solids with and without a van der Waals Correction.
S057
Bartel CJ et al. (2025). Topological Descriptors for the Electron Density of Inorganic Solids.
S058
Monty R. Cosby, Christopher J. Bartel, Adam A. Corrao, Gerbrand Ceder (2021). Salt effects on Li-ion exchange kinetics and activation energies - systematic in situ synchrotron diffraction studies.
S059
Erik G. Rognerud, Christopher L. Rom, Paul K. Todd, Christopher J. Bartel, et al. (2019). Kinetically Controlled Low-Temperature Solid-State Metathesis of Manganese Nitride Mn3N2.
S060
Gia Thinh Tran, Allison Wustrow, Daniel O'Nolan, Christopher J. Bartel, et al. (2023). Selective Synthesis of Defect-Rich LaMnO3 by Low-Temperature Anion Cometathesis.
S061
Jane Schlesinger, Simon Hjaltason, Nathan J. Szymanski, Christopher J. Bartel (2026). Thermodynamic assessment of machine learning models for solid-state synthesis prediction.
S062
Pandey R, Bartel CJ et al. (2021). Data-centric approach to improve machine learning models for inorganic materials.
S063
Bartel, Clber, Mukhopadhyay, Birgisson, Key, Barin, Simmonds, Stolt, Schelhas, Persson, Holder, Toney, Toberer, Neilson (2018). Redox-Mediated Stabilization in Zinc Molybdenum Nitrides.
S064
Christopher J. Bartel, Christopher L. Muhich, Alan W. Weimer, Charles B. Musgrave (2016). Aluminum Nitride Hydrolysis Enabled by Hydroxyl-Mediated Surface Proton Hopping.
S065
Bartel CJ, Kim J,ండ Sun W, Ceder G (2023). Thermodynamic and Kinetic Barriers Limiting Solid-State Reactions Resolved through In Situ Synchrotron Studies of Lithium Halide Salts.
S066
Bartel CJ, Rumptz JR, Weimer AW, Holder AM, Musgrave CB (2020). Selective metathesis synthesis of MgCr2S4 by control of thermodynamic driving forces.
S067
Bartel, Kim, Ceder (2020). Computational investigation of chalcogenide spinel conductors for all-solid-state Mg batteries.
S068
Liu, Szymanski, Noordhoek, Shin, Kim, Bartel, Jalan (2024). Unraveling the Growth Dynamics of Rutile Sn1-xGexO2 Using Theory and Experiment.
S069
Lannerd, Szymanski, Bartel (2026). Thermodynamics of proton insertion across the perovskite-brownmillerite transition in La0.5Sr0.5CoO3-delta.
S070
Schlesinger, Hjaltason, Szymanski, Bartel (2026). Thermodynamic assessment of machine learning models for solid-state synthesis prediction.
S071
Armand J. Lannerd, Nathan J. Szymanski, Christopher J. Bartel (2026). Thermodynamics of proton insertion across the perovskite-brownmillerite transition in La0.5Sr0.5CoO3-delta.
S072
Elisabetta Arca, Stephan Lany, John D. Perkins, Christopher J. Bartel, Aaron M. Holder, Andriy Zakutayev (2018). Redox-Mediated Stabilization in Zinc Molybdenum Nitrides.
S073
Bartel, Rumptz, Weimer, Holder, Musgrave (2019). High-Throughput Equilibrium Analysis of Active Materials for Solar Thermochemical Ammonia Synthesis.
S074
Singstock, Bartel, Holder, Musgrave (2020). High-Throughput Analysis of Materials for Chemical Looping Processes.
S075
Gathmann, Bartel, Grabow, Abdelrahman, Frisbie, Dauenhauer (2024). Dynamic Promotion of the Oxygen Evolution Reaction via Programmable Metal Oxides.
S076
Szymanski NJ, Bartel CJ, Zeng Y, Tu Q, Ceder G (2023). Adaptively driven X-ray diffraction guided by machine learning for autonomous phase identification.
S077
Szymanski NJ, Bartel CJ, Zeng Y, Luo Y, Ceder G (2023). Precursor recommendation for inorganic synthesis by machine learning materials similarity from scientific literature.
S078
Szymanski NJ, Zeng Y, Huo H, Bartel CJ, Kim H, Ceder G (2022). Machine-Learning Rationalization and Prediction of Solid-State Synthesis Conditions.
S079
Szymanski, Smith, Daoutidis, Bartel (2025). Topological Descriptors for the Electron Density of Inorganic Solids.
S080
Bartel CJ, Szymanski NJ, Zeng Y, Ceder G (2025). Establishing baselines for generative discovery of inorganic crystals.
S081
Szymanski, Bartel, Zeng, Tu, Ceder (2021). Probabilistic Deep Learning Approach to Automate the Interpretation of Multi-phase Diffraction Spectra.
S082
Bryan R. Goldsmith, Jacques A. Esterhuizen, Jin-Xun Liu, Christopher J. Bartel, Christopher Sutton (2018). Machine learning for heterogeneous catalyst design and discovery.
S083
Yi-Ting Cheng, Eshaan S. Patheria, Colin T. Morrell, Christopher J. Bartel (2025). Electronic structure perspective on cation and anion redox in Li2FeS2.
S084
Bartel CJ, Kim J,ండ Sun W, Ceder G (2021). Synthetic accessibility and stability rules of NASICONs.
S085
Todd PK, McDermott MJ, Rom CL, Corber AA, Bartel CJ et al. (2020). Sequential pairwise reactions dictate phase evolution in the solid-state synthesis of multicomponent ceramics.
S086
Dasuni Rathnaweera, Xudong Huai, Ramesh Kumar, Christopher J. Bartel, et al. (2025). Antibonding and electronic instabilities in GdRu2X2 (X = Si, Ge, and Sn): a new pathway toward developing centrosymmetric altermagnets.
S087
Kevin Cruse, Viktoriia Baibakova, Maged Abdelsamie, Christopher J. Bartel, Gerbrand Ceder (2023). Text Mining the Literature to Inform Experiments and Rationalize Impurity Phase Formation for BiFeO3.
S088
Bartel CJ, Zeng Y, Szymanski NJ, Tu Q, Ceder G (2024). Quantifying the regime of thermodynamic control for solid-state reactions during ternary metal oxide synthesis.
S089
Akira Miura, Christopher J. Bartel, Yosuke Goto, Yusuke Moriyasu, Chikako Moriyoshi, Yoshihiro Kuroiwa, Wenhao Sun, Gerbrand Ceder (2021). Observing and Modeling the Sequential Pairwise Reactions that Drive Solid-State Ceramic Synthesis.
S090
Monty R. Cosby, Christopher J. Bartel, Adam A. Corrao, Gerbrand Ceder (2023). Thermodynamic and Kinetic Barriers Limiting Solid-State Reactions Resolved through In Situ Synchrotron Studies of Lithium Halide Salts.
S091
Bartel CJ, Zeng Y, Szymanski NJ, Tu Q, Ceder G (2023). Assessing Thermodynamic Selectivity of Solid-State Reactions for the Predictive Synthesis of Inorganic Materials.
S092
Nathan J. Szymanski, Young-Woon Byeon, Yingzhi Sun, Christopher J. Bartel, Gerbrand Ceder (2024). Quantifying the regime of thermodynamic control for solid-state reactions during ternary metal oxide synthesis.
S093
Szymanski, Warren, Weimer, Bartel (2025). Cation vacancies mediate thermochemical water splitting with iron aluminates.
S094
Abdelsamie, Hong, Cruse, Bartel, Baibakova, Trewartha, Jain, Ceder, Sutter-Fella (2023). Combining text mining, in situ characterization, and ab initio calculations to rationalize BiFeO3 crystallization pathways.
S095
Kingsbury RS, Rosen AS, Gupta AS, Munro JM, Dwaraknath SS, Horton MK, Ong SP (2022). Performance comparison of r2SCAN and SCAN metaGGA density functionals for solid materials via an automated, high-throughput computational workflow.
S096
Mlorber V, Bartel CJ (2024). Accelerating the prediction of inorganic surfaces with machine learning interatomic potentials.
S097
Kyle Noordhoek, Christopher J. Bartel (2024). Accelerating the prediction of inorganic surfaces with machine learning interatomic potentials.
S098
Samantha L. Millican, Jacob M. Clary, Christopher J. Bartel, et al. (2020). Alloying behavior of wide band gap alkaline-earth chalcogenides.
S099
Bartel CJ et al. (2023). Interpretable machine learning to understand the performance of semilocal density functionals for materials thermochemistry.
S100
S. P. Sullivan, Seungjun Lee, Nathan J. Szymanski, Christopher J. Bartel (2025). Computational search for materials having a giant anomalous Hall effect in the pyrochlore and spinel crystal structures.
S101
Nathan J. Szymanski, Christopher J. Bartel, Yan Zeng, Gerbrand Ceder (2021). Probabilistic Deep Learning Approach to Automate the Interpretation of Multi-phase Diffraction Spectra.
S102
Haoyan Huo, Christopher J. Bartel, Tanjin He, Gerbrand Ceder (2022). Machine-Learning Rationalization and Prediction of Solid-State Synthesis Conditions.
S103
Nathan J. Szymanski, Pragnay Nevatia, Christopher J. Bartel, Gerbrand Ceder (2023). Autonomous and dynamic precursor selection for solid-state materials synthesis.
S104
Fengdeng Liu, Nathan J. Szymanski, Kyle Noordhoek, Christopher J. Bartel, et al. (2024). Unraveling the Growth Dynamics of Rutile Sn1-xGexO2 Using Theory and Experiment.
S105
Bartel CJ et al. (2026). Thermodynamic assessment of machine learning models for solid-state synthesis prediction.
S106
Bartel et al. (2022). High-Throughput Selection and Experimental Realization of Two New Ce-Based Nitride Perovskites: CeMoN3 and CeWN3.
S107
Bartel et al. (2025). Origins of chalcogenide perovskite instability.
S108
Bartel, Clary, Sutton, Vigil-Fowler, Goldber, Musgrave, Lany, Holder (2020). Inorganic Halide Double Perovskites with Optoelectronic Properties Modulated by Sublattice Mixing.
S109
Bartel et al. (2021). Data-centric approach to improve machine learning models for inorganic materials.
S110
Bartel et al. (2021). Solid-State Calcium-Ion Diffusion in Ca1.5Ba0.5Si5O3N6.
S111
Talley KR, Bartel CJ, Sherbondy R, Zakutayev A, Holder AM (2022). High-Throughput Selection and Experimental Realization of Two New Ce-Based Nitride Perovskites: CeMoN3 and CeWN3.
S112
Abdelsamie A, Bartel CJ et al. (2023). Text Mining the Literature to Inform Experiments and Rationalize Impurity Phase Formation for BiFeO3.
S113
Deng B, Zhong P, Bartel CJ, Ceder G (2024). Foundational Machine Learning Interatomic Potential to Study Li-Ion Battery Cathode Phase Transformation with Charge Transfer.
S114
Bartel CJ et al. (2025). Origins of chalcogenide perovskite instability.
S115
Bartel CJ et al. (2024). Synthesis, Electronic Structure, and Redox Chemistry of Li2MnP2S6, a Candidate High-Voltage Cathode Material.
S116
Bartel et al. (2021). Expanding the Ambient-Pressure Phase Space of CaFe2O4-Type Sodium Postspinel Host-Guest Compounds.
S117
Bartel et al. (2021). Layered Transition Metal Oxides as Ca Intercalation Cathodes: A Systematic First-Principles Evaluation.
S118
Bartel CJ et al. (2018). Finding Patterns, Correlations, and Descriptors in Materials Data Using Subgroup Discovery and Compressed Sensing.
S119
Bartel CJ et al. (2022). Phase Stability and Kinetics of Topotactic Dual Ca2+-Na+ Ion Electrochemistry in NaSICON NaV2(PO4)3.
S120
Bartel CJ, Koettgen J, Ong SP (2020). Computational investigation of chalcogenide spinel conductors for all-solid-state Mg batteries.
S121
Bartel CJ et al. (2021). Expanding the Ambient-Pressure Phase Space of CaFe2O4-Type Sodium Postspinel Host-Guest Compounds.
S122
Bartel CJ et al. (2021). Salt effects on Li-ion exchange kinetics and activation energies - systematic in situ synchrotron diffraction studies.
S123
Abdelsamie A, Bartel CJ et al. (2023). Combining text mining, in situ characterization, and ab initio calculations to rationalize BiFeO3 crystallization pathways.
S124
Bartel CJ et al. (2017). Rapid Computational Screening of Materials for Water Splitting Using Ab Initio and Machine Learned Models.
S125
Sullivan SP, Bartel CJ (2025). Computational search for materials having a giant anomalous Hall effect in the pyrochlore and spinel crystal structures.
S126
Millican SL, Bartel CJ et al. (2020). Alloying behavior of wide band gap alkaline-earth chalcogenides.
S127
Koettgen J, Bartel CJ, Ong SP (2020). First-Principles Study of CaB12H12 as a Potential Solid-State Conductor for Ca.
S128
Bartel CJ et al. (2025). Antibonding and Electronic Instabilities in GdRu2X2 (X = Si, Ge, Sn).
S129
Bartel CJ et al. (2026). Thermodynamics of proton insertion across the perovskite-brownmillerite transition in La0.5Sr0.5CoO3-delta.
S130
Liu Y, Bartel CJ et al. (2024). Unraveling the Growth Dynamics of Rutile Sn1-xGexO2 Using Theory and Experiment.
S131
Bartel CJ, Millican SL, Deml AM, Rumptz JR, Tumas W, Weimer AW, Lany S, Musgrave CB, Holder AM (2018). Physical descriptor for the Gibbs energy of inorganic crystalline solids and temperature-dependent materials chemistry.
S132
Bartel CJ, Weimer AW, Lany S, Musgrave CB, Holder AM (2019). The role of decomposition reactions in assessing first-principles predictions of solid stability.
S133
Bartel CJ, Rumptz JR, Weimer AW, Holder AM, Musgrave CB (2019). High-throughput equilibrium analysis of active materials for solar thermochemical ammonia synthesis.
// playbooks/
5 analytical recipes
Step-by-step recipes that wire constructs to engines. An MCP-aware agent runs them end-to-end.
B Cross-Domain Literature Survey
3 steps · 2 minutes
Literature synthesis across all 7 Bartel research domains. Uses unsupervised clustering to identify natural construct groupings, then probes cross-domain relationships via correlation and regression.
engine.kmeans_clusteringengine.correlation_matrixengine.ols_regression
B Perovskite Formability Screening
4 steps · 2 minutes
Screen ABX3 compositions for perovskite formability using the revised tolerance factor (tau), geometric descriptors, and ML classifiers. Combines closed-form calculation with statistical validation.
engine.logistic_regressionengine.correlation_matrixengine.random_forestengine.tolerance_factor_calculator
B Quick Start — Bartel Comp Materials
1 steps · 1–3 minutes
Basic analysis workflow for the bartel_comp_materials domain.
engine.logistic_regression
B Stability Prediction Benchmark
4 steps · 3 minutes
Compare ML approaches for predicting thermodynamic stability (formation energy, energy above hull). Benchmarks linear models against gradient boosting and CHGNet neural network potentials.
engine.pydmclab_ml_potential_relaxationengine.correlation_matrixengine.gradient_boostingengine.ridge_regression
B Synthesis Feasibility Assessment
4 steps · 2 minutes
Evaluate synthesis feasibility for target materials by combining thermodynamic selectivity analysis with ML classifiers trained on reaction outcomes. References Bartel's synthesis assessment tools.
engine.logistic_regressionengine.correlation_matrixengine.synth_assess_selectivityengine.random_forest
// playbook step bodies live in the .pax archive; download to inspect.
// relationships.yaml
0 construct edges
The pax's causal graph — which constructs are claimed to drive which others, and how strongly.
// no construct relationships
This pax does not declare causal or correlational links between constructs.
// pax.yaml manifest
name: bartel-comp-materials
version: 1.0.12
pax_type: field
published_by: Praxis Agent
domain: autonomous_synthesis
constructs:
  - discovery_acceleration_factor
  - band_gap
  - bulk_modulus
  - crystal_structure_representation
  - gnn_interatomic_potential
  - mean_absolute_error_materials
  - formation_energy_per_atom
  - thermodynamic_stability
  - revised_tolerance_factor
  - energy_above_hull
  - neural_network_potential
  - synthesis_success_rate
  - thermodynamic_selectivity
  - perovskite_formability
  - intercalation_voltage
  - force_field_mae
  - reaction_driving_force
  - xrd_phase_identification_accuracy
  - oxygen_evolution_overpotential
  - persistent_homology_descriptor
  # … 69 more
engines:
  - logistic_regression
  - random_forest
  - gradient_boosting
  - ridge_regression
counts:
  constructs: 89
  findings: 283
  propositions: 0
  playbooks: 5
  sources: 133