High temperature Raman band contours and vibrational analysis of arsenic oxide vapors

Raman spectra of vapors over arsenic oxide have been obtained at temperature up to 1200 K. Three Raman bands not reported previously have been observed and vibrational–rotational contours for E and F species fundamentals of As4O6 have been resolved. A band of medium intensity at 410 cm−1 was found to be polarized and its relatively high intensity was attributed to Fermi resonance between the 2ν6 and the ν2 modes. A valence force field calculation has been carried out, and the mean amplitudes of vibration and Cartesian displacements of As4O6 have been evaluated. The vibrations have been compared with AsO3 fundamentals by a group theoretical correlation method.