Raman studies of solid hydrogen cyanide (HCN, DCN) and of HCN argon matrices

Abstract

Abstract Raman spectra of single crystal-like oriented solid HCN and DCN, as well as of HCN molecules and clusters in argon matrices, have been recorded and analysed with respect to both so far uninterpreted spectral features reported in the literature and to the applicability of Raman experiments for studying molecular clusters in inert gas matrices. The main results obtained are: (i) splitting of both the intramolecular bending modes and librations of solid HCN has to be interpreted in terms of TO/LO splitting rather than site group splitting; (ii) the nature of the phase transition at 170 K reported as tI6 to oI6 must be doubted; and (iii) the previous results of HCN(DCN)/Ar matrices obtained by IR studies are confirmed.