Vibrational normal modes of SiO2. I. α and β quartz

Abstract

A theoretical study of the vibrational modes of α and β quartz has been carried out, using some recent experimental results on the β form. It is shown that a single valence force field can account for the optical frequencies of both crystalline forms. The infrared and Raman intensities were also calculated from atomic displacements, using the method of Kleinman and Spitzer; the results seem satisfactory on the whole.