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arXiv · 1012.3603

Ab Initio determination of Cu 3d orbital energies in layered copper oxides

Liviu Hozoi·Liudmila Siurakshina·Peter Fulde·Jeroen van den Brink
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Abstract

It has long been argued that the minimal model to describe the low-energy physics of the high-Tc superconducting cuprates must include copper states of other symmetries besides the canonical x2-y2 one, in particular the z2 orbital. Experimental and theoretical estimates of the energy splitting of these states vary widely. With a novel ab initio quantum chemical computational scheme we determine these energies for a range of copper-oxides and -oxyclorides, determine trends with the apical Cu-ligand distances and find excellent agreement with recent Resonant Inelastic X-ray Scattering measurements, available for La2CuO4, Sr2CuO2Cl2, and CaCuO2.

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Liviu Hozoi, Liudmila Siurakshina, Peter Fulde, Jeroen van den Brink. 2010-12-16. Ab Initio determination of Cu 3d orbital energies in layered copper oxides. https://doi.org/10.1038/srep00065(2011)

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