Influence of Dispersion Interactions on the Polymorphic Stability of Crystalline Oxides

Abstract

The accurate determination of relative phase stabilities using DFT methods is a significant challenge when some of these can vary by only a few kJ/mol. Here, we demonstrate that for a selection of oxides (TiO2, MnO2, and ZnO) the inclusion of dispersion interactions, accomplished using the DFT-D3 correction scheme, allows for the correct ordering and an improved calculation of the energy differences between polymorphic phases. The energetic correction provided is of the same order of magnitude as the energy difference between phases. D3-corrected hybrid functionals systematically yield results closest to experiment. We propose that the inclusion of dispersion interactions makes a significant contribution to the relative energetics of polymorphic phases, especially those with different densities, and should therefore be included for calculations of relative energies using DFT methods.

London Dispersion Effects on the Structure and Properties of Nonlinear Optical BiB3O6 Crystal

“…DFT-D type corrections were usually proposed based on model sets of molecular systems and have been applied to various system ranging from rare gas, simple molecules, to large systems of macromolecular, polymer, proteins, surfaces and interfaces. [2,3,7,8] However, it is less widely applied to ionic solid, [16][17][18][19] but the importance of its inclusion has already be demonstrated as that when studying the polymorphisms of CsX (X = Halogen atoms) or TiO 2 , wrong ground states will be reached without DFT-D type corrections. [16][17][18] Monoclinic BiB 3 O 6 crystal (BiBO, α-phase, Space group C2) [20] is an important nonlinear optical (NLO) material having large NLO coefficients [21,22] and high efficiency frequency conversion has been achieved.…”

Phase transition behaviour and mechanism of 2D TiO2(B) nanosheets through water-mediated removal of surface ligands

“…Evaluating the phase stability of a metastable phase and comprehending the phase transition behaviour are a precondition for materials design, synthesis and application. 9–11…”

“…Evaluating the phase stability of a metastable phase and comprehending the phase transition behaviour are a precondition for materials design, synthesis and application. [9][10][11] For example, TiO 2 (B) is a metastable phase and a naturally occurring polymorph of TiO 2 . 12 When the application scenarios call for maintaining the crystal structure of TiO 2 (B), phase transition should be avoided.…”