XANES Study of Copper Valence and Structure in High Tc Superconducting Oxides
The question of Cu3+ and role it may play in the mechanism of the HTSC in the perovskites recently has been examined in depth employing XPS and XANES techniques [1–5]. The Cu 2p XPS and valence band emission from CuO and YBa2 Cu3O7-x when discussed along with the CuL3, XANES in these clearly ruled out the presence of Cu3+ and established that the holes are instead situated in the oxygen band. This is further reinforced by the presence of additional peak in the O ls XPS emission. Measurements and one-electron full-multiple scattering calculations on the CuK XANES establish that the best fits to experimental data are obtained employing the 3d10 configuration for copper . The question of alternative structure proposed by Reller, Bednorz and Muller is also examined and rejected through these calculations.
KeywordsXANES Spectrum Oxygen Band Characteristic Spectral Feature Fourth Shell Final State Configuration
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- 5.A. Bianconi, A. Clozza, A. Congiu Castellano, S. Delia Longa, M. De Santis, A. Di Cicco, K.B. Garg, P. Delogu, A. Gargano, R. Giorgi, P. Lagarde, A.M. Flank and A. Marcelli, Proc. 14th Int. Conf. on X-ray and Inner-shell Processes, Paris Sept. 14–18, 1987 (France).Google Scholar
- 10.P.J. Durham, W.M. Temmerman, and G.M. Stocks, Proceeding of the 14th International Conference on X-ray and Inner-shell Processes, Paris Sept. 14–18, 1987 (France).Google Scholar