Energy and polarization dependence of resonant inelastic X-ray scattering in Nd2CuO4

We report the energy and polarization dependence of resonant inelastic X-ra y scattering from Nd2CuO4. An energy loss feature at similar to 6 eV is obs erved in the vicinity of the Cu K-edge. Numerical calculations based on the Anderson impurity model identify this as a charge transfer excitation to t he anti-bonding state. The incident polarization is shown to select the int ermediate states participating in the resonance process. Resonances are obs erved at 8990 and 9000 eV with the incident polarization perpendicular and parallel to the CuO planes, respectively. In contrast to our single-site mo del calculations, no resonances are observed associated with the 1s3d(10)L intermediate states, suggesting that non-local effects play a role. (C) 200 0 Elsevier Science Ltd. All rights reserved.