RAMAN-SCATTERING FROM VO2 SINGLE-CRYSTALS - A STUDY OF THE EFFECTS OF SURFACE OXIDATION

VO2 single crystals were studied in an effort to resolve the differences that are present in two previous reports on the Raman spectra of VO2. We find that surface oxidation effects that change the stoichiometry of the material at the surface layer produce large shifting of the Raman spectral peaks. The experimental evidence is presented and the relation to the previous Raman studies of VO2 are discussed. © 1990 The American Physical Society.