Raman scattering study of β-Sr0.33V2O5 in charge disordered and ordered phase

• Published in: Journal of physics. Condensed matter Vol. 18; no. 32; pp. 7779 - 7787
• Main Authors: Popović, Z V, Kontos, A G, Raptis, Y S, Isobe, M, Ueda, Y
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 16.08.2006; Institute of Physics
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Infrared and raman spectra and scattering; Lattice dynamics; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Other nonmetallic inorganics; Phonon states and bands, normal modes, and phonon dispersion; Phonons and vibrations in crystal lattices; Physics; Raman spectra; Charge ordering; Strontium Vanadates; Phonon mode; Electron delocalization; Phonon damping; Bronze type compound; Mixed valence
• ISSN: 0953-8984; 1361-648X
• DOI: 10.1088/0953-8984/18/32/024

Polarized Raman spectra of the strontium vanadium oxide bronze beta-Sr0.33V2O5 are measured in the temperature range between 300 and 77 K. The charge ordering phase transition at about 165 K is characterized by the appearance of new Raman-active modes in the spectra, as well as through an abrupt change of the phonon frequencies and dampings. The Raman scattering spectra of beta-Sr0.33V2O5 in the charge disordered phase are in apparent resemblance with those of alpha'-NaV2O5, which suggests that there is a similar charge-phonon dynamics in both compounds. We also suggest that the electrons are delocalized into V1-O5-V3 orbitals in the mixed valence state of beta-Sr0.33V2O5.