Abstract
We report resonant inelastic x-ray scattering studies of electronic excitations in a wide variety of cuprate compounds. Specifically, we focus on the charge-transfer type excitation of an electron from a bonding molecular orbital to an antibonding molecular orbital in a copper oxygen plaquette. Both the excitation energy and the amount of dispersion are found to increase significantly as the copper oxygen bond length is reduced. We also find that the estimated bond-length dependence of the hopping integral is much stronger than that expected from tight-binding theory.
- Received 7 July 2004
DOI:https://doi.org/10.1103/PhysRevB.70.205128
©2004 American Physical Society