Investigation on the stability, mechanism and electronic properties of rutile TiO2 via first-principle calculations

Abstract

Through first-principles calculations, the structural stability, electrical properties, and mechanical characteristics of TiO2 in the P42/mcm space group under varying external pressures were explored. The dynamical and elastic stability of TiO2 with P42/mcm space group are evaluated based on calculated results of phonon dispersion curves and elastic constants. Furthermore, the evaluation of the theoretical elastic modulus, derived through the stress-strain method, reveals a notable anisotropic characteristic in the TiO2 structure. In light of the ideal strength values ascertained through a range of strain conditions, coupled with the two-dimensional electron localization function maps pertinent to various pivotal structural models, the fundamental mechanism that dictates the mechanical properties of the TiO2 structure has been pinpointed. Meanwhile, the contributions of oxygen (O) and titanium (Ti) atoms to the conduction and valence bands in the band structure of TiO2 have been systematically analyzed. The results of the research will aid in exploring the inherent mechanical and electrical properties of TiO2 compounds.