Abstract
Ab initio molecular orbital calculations of oxygen 2p hole states of small CuO clusters representing the chains and planes in YBa2Cu3O7−x are reported. The results suggest that the absorption observed at 0.37 eV in reflectivity studies of YBa2Cu3O7−x may be due to excitation of these holes between inequivalent oxygen sites.
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Curtiss, L.A., Tam, S.W. Theoretical investigation of possible low-lying electronic excitations in YBa2Cu3O7−x. Journal of Materials Research 3, 1269–1272 (1988). https://doi.org/10.1557/JMR.1988.1269
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DOI: https://doi.org/10.1557/JMR.1988.1269