TiO2 has tremendously drawn the attention of researchers from the photocatalytic to photovoltaic groups. To explore further avenues of applications, it is important to understand various properties and the phase transformations of TiO2 polymorphs at ambient conditions. The detailed study on the phase transitions (pressure induced) of the low-pressure polymorphs (rutile, anatase, brookite and columbite) of TiO2 is surprisingly missing in the literature. In view of the above, we have carried out ab-initio calculations on these four polymorphs of TiO2 using full potential linearized augmented plane wave [FP-LAPW] method to study the structural phase transitions and elastic properties. The transition pressures at 0 K among anatase (A), rutile (R), brookite (B) and columbite (C) are found out to be -2.4 GPa (A-B), 5.3 GPa (A-R), 5.7 GPa (A-C), 8.7 GPa (R-C), 10.7 GPa (B-C) and 11.6 GPa (B-R) respectively. The elastic properties at P = 0 GPa are examined through computation of elastic constants for all polymorphs. All the polymorphs are found to be mechanically stable. The anisotropy in shear moduli and directional dependence of Young's modulus are also investigated for all the polymorphs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.