The Strong Electron Correlation Effects in XAFS Spectra of HTSC Cuprates

P.V. Avramov; S.G. Ovchinnikov

doi:doi:10.1051/jp4/1997158

Issue		J. Phys. IV France Volume 7, Number C2, Avril 1997 Proceedings of the 9th International Conference on X-Ray Absorption Fine Structure


Page(s)		C2-183 - C2-185
DOI		https://doi.org/10.1051/jp4/1997158

Proceedings of the 9th International Conference on X-Ray Absorption Fine Structure

J. Phys. IV France 7 (1997) C2-183-C2-185
DOI: 10.1051/jp4/1997158

The Strong Electron Correlation Effects in XAFS Spectra of HTSC Cuprates

P.V. Avramov and S.G. Ovchinnikov

L. V. Kirenskii Institute of Physics, Siberian Branch of Russian Academy of Sciences, Krasnoyarsk 660036, Russia

Abstract
Theoretical XAFS spectra of highly correlated copper oxides have been presented as a product of a single-election part obtained by the SCF Xα- SW method, and a multi-electron part obtained by the multi-band multi-electron p-d model. Trie main line of CuK-spectram of La₂CuO₄ was aligned to the Cud¹⁰ L - configuration and the single satellite line was aligned to the Cud⁹. Comparison of the theoretical data with the experimental ones shows that the ground state of the two-holes in the CuO₄ doped cell is triplet. The last conclusion has been confirmed by analysis of CuL_2,3^- spectra of two-hole impurity states of doped CuO₄ cell. Another interesting future of CuL_2,3^- spectra - a peak 2.8 eV higher the threshold was aligned to the transitions into quasi-stationary states due to existence of a high barrier in the Cud- state potential.