Electronic structure of the two-dimensional Heisenberg antiferromagnet VOCl: a multi-orbital Mott insulator

Abstract

We have studied the electronic structure of the two-dimensional Heisenberg antiferromagnet VOCl using photoemission spectroscopy and density functional theory including local Coulomb repulsion. From calculated exchange integrals and the observed energy dispersions we argue that the degree of one-dimensionality regarding both the magnetic and electronic properties is noticeably reduced compared to the isostructural compounds TiOCl and TiOBr. Also, our analysis provides conclusive justification to classify VOCl as a multi-orbital Mott insulator. In contrast to the titanium based compounds density functional theory here gives a better description of the electronic structure. However, a quantitative account of the low-energy features and detailed line shapes calls for further investigations including dynamical and spatial correlations.

7 pages, 6 figures

References in corpus (6)

• Orbital-Selective Mott transition out of band degeneracy lifting
• Strong Magneto-elastic coupling in VOCl: Neutron and synchrotron powder x-ray diffraction study
• Unusual quasi-one-dimensional electron dispersions in the spin-1/2 quantum magnet TiOCl
• Microscopic model for transitions from Mott to spin-Peierls insulator in TiOCl
• Momentum-resolved single-particle spectral function for TiOCl from a combination of density functional and variational cluster calculations
• Microscopic theory for the incommensurate transition in TiOCl