Hydrostatic and [001] Uniaxial Pressure on Anatase TiO₂ by Periodic B3LYP-D* Calculations

Abstract

The effect of high hydrostatic and [001] uniaxial pressures on TiO 2 anatase was studied under the framework of periodic calculations with the inclusion of DFT-D2 dispersion potential adjusted for this system (B3LYP-D*). The role of dispersion in distorted unit cells was evaluated in terms of lattice parameters, elastic constants, equation of state, vibrational properties, and electronic properties (band structure and density of states). A more reliable description at high pressures was achieved because the B3LYP-D* presented an improvement in all properties for undistorted bulk over conventional B3LYP and B3LYP-D. From density of states analysis, we observed that the contribution of crystalline orbitals to the edge of valence and conduction bands changed within applied pressure. The studied distortions can give some insight into behavior of electronic and structural properties due to local stress in anatase bulk from doping, defects, and physical tensions in nanometric forms.

Antimicrobial activity of TiO2:Ag nanocrystalline heterostructures: Experimental and theoretical insights

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Uniaxial pressure-induced half-metallic ferromagnetic phase transition inLaMnO3

“…We will address this particular aspect and highlight the possible coexistence of magnetic and structural features that occur for a specific range of uniaxial pressure near the phase transition. The application of compressive uniaxial strain has been investigated for a large variety of materials, with the goal of tuning and optimizing the electronic and magnetic properties [33][34][35], but only a few studies on LaMnO 3 have been reported to-date. These studies were focused on providing an interpretation of experiments on epitaxially grown LaMnO 3 [36,37] and therefore, only applied small uniaxial strains of the order of 2% or less were considered.…”

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