Correlation effects on the electronic structure of TiOCl: a NMTO+DMFT study

TL;DR

This study employs a combined NMTO and DMFT approach to analyze the electronic structure of TiOCl, revealing correlation-induced Hubbard bands consistent with experimental photo-emission data.

Contribution

It introduces a novel application of NMTO+DMFT to TiOCl, providing detailed insight into its Mott insulating state and spectral features.

Findings

Identification of upper and lower Hubbard bands in TiOCl

Spectral function matches recent photo-emission spectra

Orbital polarization influences valence band structure

Abstract

Using the recently developed N-th order muffin-tin orbital-based downfolding technique in combination with the Dynamical Mean Field theory, we investigate the electronic properties of the much discussed Mott insulator TiOCl in the undimerized phase. Inclusion of correlation effects through this approach provides a description of the spectral function into an upper and a lower Hubbard band with broad valence states formed out of the orbitally polarized, lower Hubbard band. We find that these results are in good agreement with recent photo-emission spectra.