Site-selected O2pdensities of states inNaV2O5determined from angular-dependent x-ray absorption and emission spectra

We present angular-dependent soft x-ray absorption and emission spectra for the highly anisotropic material ${\mathrm{NaV}}_2{\mathrm{O}}_5,$ which contains three inequivalent oxygen sites located around the V atoms. The polarization direction of the incident photon beam was varied with respect to the crystal axes to obtain strong angular dependence in both the absorption and emission data. Using both energy and angular selection, we obtain local partial densities of states information for each oxygen site, which are compared directly with theoretical results. This technique should be very useful in studies of asymmetric materials such as high-$T_c$ superconducting materials with in-plane and out-of-plane oxygen sites.