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Optical properties and electronic structure of Ca-doped alpha'-NaV2O5

C. Presura·D. van der Marel·M. Dischner·C. Geibel·R. K. Kremer
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Abstract

The dielectric function of alpha'-Na(1-x)Ca(x)V2O5 (0 < x < 20%) was measured for the a and b axes in the photon energy range 0.8-4.5 eV at room temperature. By varying the Ca-concentration we control the relative abundancy of V4+ and V5+. We observe that the intensity of the main optical absorption peak at 1 eV is proportional to the number of V5+ ions. This rules out the interpretation as a V4+ d-d excitation, and it establishes that this is the on-rung bonding-antibonding transition.

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C. Presura, D. van der Marel, M. Dischner, C. Geibel, R. K. Kremer. 2000-05-31. Optical properties and electronic structure of Ca-doped alpha'-NaV2O5. https://doi.org/10.1103/physrevb.62.16522

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