An interpretable formula for lattice thermal conductivity of crystals

TL;DR

This paper presents an accurate, fast, and interpretable formula for predicting lattice thermal conductivity of crystals, enabling efficient material screening and insights into heat transport mechanisms.

Contribution

The study introduces a novel, physically grounded formula that predicts kL for thousands of materials with high accuracy and speed, surpassing traditional complex phonon calculations.

Findings

Achieves mean relative error of 8.97% in predictions.

Predicts high and low kL values for undiscovered materials.

Provides insights into microscopic heat transport mechanisms.

Abstract

Lattice thermal conductivity (kL) is a crucial physical property of crystals with applications in thermal management, such as heat dissipation, insulation, and thermoelectric energy conversion. However, accurately and rapidly determining kL poses a considerable challenge. In this study, we introduce an formula that achieves high precision (mean relative error=8.97%) and provides fast predictions, taking less than one minute, for kL across a wide range of inorganic binary and ternary materials. Our interpretable, dimensionally aligned and physical grounded formula forecasts kL values for 4,601 binary and 6,995 ternary materials in the Materials Project database. Notably, we predict undiscovered high kL values for AlBN2 (kL=101 W/ m/ K) and the undetectedlow kL Cs2Se (kL=0.98 W/ m/ K) at room temperature. This method for determining kL streamlines the traditionally time-consuming process associated with complex phonon physics. It provides insights into microscopic heat transport and facilitates the design and screening of materials with targeted and extreme kL values through the application of phonon engineering. Our findings offer opportunities for controlling and optimizing macroscopic transport properties of materials by engineering their bulk modulus, shear modulus, and Gruneisen parameter.