The polymer backbone, as well as the SiH vibrational, modes of polysilanes (SiH)n and (SiH2)n have been identified through Raman scattering techniques. The intensities of these modes were then studied as a function of the oxidation of the sample. With time, one can see the growth of certain modes which can be identified as those arising from SiHO, SiH2O, and SiH2O2 groupings. The relationship between the stretching and bending modes of these clusters is discussed and compared to those existing in amorphous silicon hydrogen (a-SiHx). A further comparison is made with a study on the sample kept in an oxygen-free atmosphere. © 1984 The American Physical Society.