Physical descriptor for the Gibbs energy of inorganic crystalline solids and temperature-dependent materials chemistry

TL;DR

This paper introduces a simple, accurate descriptor for predicting the Gibbs energy of inorganic crystalline solids across a range of temperatures, enabling large-scale thermochemical analysis and insights into materials stability.

Contribution

The authors develop a novel SISSO-based descriptor that accurately predicts Gibbs energy for inorganic compounds at minimal computational cost, covering a wide temperature range.

Findings

Predicted Gibbs energies for ~30,000 compounds.

Generated temperature-dependent phase diagrams.

Provided new insights into materials stability and synthesizability.

Abstract

The Gibbs energy, G, determines the equilibrium conditions of chemical reactions and materials stability. Despite this fundamental and ubiquitous role, G has been tabulated for only a small fraction of known inorganic compounds, impeding a comprehensive perspective on the effects of temperature and composition on materials stability and synthesizability. Here, we use the SISSO (sure independence screening and sparsifying operator) approach to identify a simple and accurate descriptor to predict G for stoichiometric inorganic compounds with ~50 meV/atom (~1 kcal/mol) resolution, and with minimal computational cost, for temperatures ranging from 300-1800 K. We then apply this descriptor to ~30,000 known materials curated from the Inorganic Crystal Structure Database (ICSD). Using the resulting predicted thermochemical data, we generate thousands of temperature-dependent phase diagrams to provide insights into the effects of temperature and composition on materials synthesizability and stability and to establish the temperature-dependent scale of metastability for inorganic compounds.