2017/09/13 by Jamie M. Booth, Daniel W. Drumm, Booth, Jamie M. +9
Materials Science · #Transition Metal Oxide Nanomaterials #Magnetic and transport properties of perovskites and related materials #Electronic and Structural Properties of Oxides
paper · pdf · doi:10.48550/arxiv.1709.04602
Using an \ab initio approach based on the GW approximation which\nincludes strong local \k-space correlations, the Metal-Insulator\nTransition of M2 vanadium dioxide is broken down into its component parts\nand investigated. Similarly to the M1 structure, the Peierls pairing of\nthe M2 structure results in bonding-antibonding splitting which stabilizes\nstates in which the majority of the charge density resides on the Peierls\nchain. This is insufficient to drop all of the bonding states into the lower\nHubbard band however. An antiferroelectric distortion on the neighboring\nvanadium chain is required to reduce the repulsion felt by the Peierls bonding\nstates by increasing the distances between the vanadium and apical oxygen\natoms, lowering the potential overlap thus reducing the charge density\naccumulation and thereby the electronic repulsion. The antibonding states are\nsimultaneously pushed into the upper Hubbard band. The data indicate that\nsufficiently modified GW calculations are able to describe the interplay of the\natomic and electronic structures occurring in Mott metal-insulator transitions.\n