A polarizable interatomic force field for TiO$_2$ parameterized using density functional theory

TL;DR

This paper introduces a new classical force field for TiO$_2$ based on density functional theory data, accurately modeling its structural, thermodynamic, and phonon properties across different crystal phases.

Contribution

The paper presents a novel interatomic force field for TiO$_2$ parameterized with DFT data, improving simulation accuracy for various crystal structures and properties.

Findings

Force field accurately reproduces rutile TiO$_2$ properties

Good agreement with ab initio and experimental data

Describes brookite and anatase structures well

Abstract

We report a classical interatomic force field for TiO$_2$, which has been parameterized using density functional theory forces, energies, and stresses in the rutile crystal structure. The reliability of this new classical potential is tested by evaluating the structural properties, equation of state, phonon properties, thermal expansion, and some thermodynamic quantities such as entropy, free energy, and specific heat under constant volume. The good agreement of our results with {\em ab initio} calculations and with experimental data, indicates that our force-field describes the atomic interactions of TiO$_2$ in the rutile structure very well. The force field can also describe the structures of the brookite and anatase crystals with good accuracy.