An Interpretable Formula for Lattice Thermal Conductivity of Crystals

Abstract

Lattice thermal conductivity (κL) 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 κL 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 κL across a wide range of inorganic binary and ternary materials. Our interpretable, dimensionally aligned and physical grounded formula forecasts κL values for 4,601 binary and 6,995 ternary materials in the Materials Project database. Notably, we predict undiscovered high κL values for AlBN2 (κL=101 W m−1 K−1) and the undetected low κL Cs2Se (κL=0.98 W m−1 K−1) at room temperature. This method for determining κL 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 κL 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.

Keywords: An interpretable formula Lattice thermal conductivity