Density matrix approach to the orbital ordering in the spinel vanadates: A case study

Abstract

In this work we apply the density matrices approach to orbital ordering (OO) in order to study the OO of the spinel vanadates AV${}_2$O${}_4$ (A $\equiv$ Zn, Cd and Mg), which is normally believed to be responsible for the structural transition from cubic to tetragonal phase observed in these compounds. The density matrices of vanadium atoms are obtained by using {\it state-of-the-art} full-potential linearized augmented plane wave method based GGA+U calculations. In the absence of spin-orbit coupling, the present study shows the existence of anti-ferro OO in the global (local octahedral) coordinate system where $d_{xz}$ and $d_{yz}$ ($d_{xz}$+$d_{yz}$ and $d_{xz}$-$d_{yz}$) orbitals are mainly occupied at the neighboring V sites for all the compounds.

22 pages, 2 figures, 9 tables

References in corpus (11)

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Cited by in corpus (6)

• Investigation of the Thermoelectric Properties of ZnV${}_2$O${}_4$ Compound in High Temperature Region
• Self-consistent evaluation of effective Coulomb interaction of V atom and its importance to understand the comparative electronic behaviour of vanadium spinels
• Limitations of unconstrained LSDA+$U$ calculations in predicting the electronic and magnetic ground state of a geometrically frustrated ZnV${}_2$O${}_4$ compound
• Role of orbital degrees of freedom in investigating the magnetic properties of geometrically frustrated vanadium spinels
• Electronic structure study of vanadium spinels by using density functional theory and dynamical mean field theory
• The role of ionic sizes in inducing the cubic to tetragonal distortion in AV${}_2$O${}_4$ and ACr${}_2$O${}_4$ (A=Zn, Mg and Cd) compounds