RAMAN SPECTRA OF PURE AND MIXED CRYSTALS OF ACETY-LENE DEUTERATED ACETYLENE.............

Abstract

The Raman spectra of both solid phases of crystalline C2 H2 and C2 D2 have been obtained. In addition, mixed crystal spectra were investigated under conditions where one isotope was “matrix isolated” in a host lattice of the other. The spectra are consistent with the crystal structures proposed for each solid modification, and the splittings can be interpreted in terms of factor group and site group interactions. Although the intermolecular forces in solid acetylene are stronger than those in the crystals of the isoelectronic molecules N2 and CO2 the observed intensities are generally well described using the oriented gas model. The spectroscopic assignments and relative intensities will be discussed in terms of the proposed crystal structures, molecular dynamics, and intermolecular interactions.