Optical properties and electronic structure of alpha '-Na1-xCaxV2O5

Authors
Presura, C van der Marel, D Dischner, M Geibel, C Kremer, RK
Citation
C. Presura et al., Optical properties and electronic structure of alpha '-Na1-xCaxV2O5, PHYS REV B, 62(24), 2000, pp. 16522-16527
Citations number
19
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B
ISSN journal
01631829 → ACNP
Volume
62
Issue
24
Year of publication
2000
Pages
16522 - 16527
Database
ISI
SICI code
0163-1829(200012)62:24<16522:OPAESO>2.0.ZU;2-6
Abstract
The dielectric function of alpha'-Na1-xCaxV2O5 (0 less than or equal to x l ess than or equal to 20%) was measured for the a and b axes in the photon e nergy 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 inte nsity of the main optical absorption peak at 1 eV is proportional to the nu mber 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 transitio n.