Electronic excitation spectra from ab-initio band structure results for LaMO_3 (M = Cr-Ni)

TL;DR

This paper presents ab-initio calculated electron excitation spectra for LaMO_3 (M=Cr-Ni), demonstrating good agreement with experiments and highlighting the significance of transition metal-oxygen interactions over multiplet effects.

Contribution

The study provides ab-initio spectra for LaMO_3 series and challenges previous assumptions about the role of multiplet interactions in these materials.

Findings

Good agreement between calculated and experimental spectra

Transition metal-oxygen interactions are crucial for spectral features

Suggests a smaller U/t ratio than previously believed

Abstract

We present calculated electron excitation spectra for the LaMO_3 series (M=Cr-Ni) obtained within ab-initio band structure calculations for the real geometric and magnetic structures. The calculated results show good agreement with the experimentally obtained spectra. This suggests that the transition metal-transition metal interactions via the oxygen atom play an important role in determining the spectroscopic features and indicates a smaller value of U/t than has been believed so far. The present approach undermines the importance of multiplet interactions which otherwise play an important role within various single impurity models.