1 3 N ov 2 00 2 Charge and sodium ordering in β − Na 0 . 33 V 2 O 5 Raman and optical spectroscopy
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چکیده
Polarized Raman and optical spectra for the quasi-one dimensional metallic vanadate β−Na0.33V2O5 are reported for various temperatures. The spectra are discussed in the light of the sodium and charge ordering transitions occurring in this material, and demonstrate the presence of strong electron-phonon coupling.
منابع مشابه
Ja n 20 01 Charge - ordering phase transition and order - disorder effects in the Raman spectra of NaV
In the ac polarized Raman spectra of NaV 2 O 5 we have found anomalous phonon broadening, and an energy shift of the low-frequency mode as a function of the temperature. These effects are related to the breaking of translational symmetry, caused by electrical disorder that originates from the fluctuating nature of the V 4.5+ valence state of vanadium. The structural correlation length, obtained...
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