Infrared Spectra of Crystalline C_2H_2, C_2HD, and C_2D_2

Publication

Reference: Bottger G. L., Eggers Jr. D. F. (1964). Infrared Spectra of Crystalline $C_2H_2$, $C_2HD$, and $C_2D_2$. J. Chem. Phys., 40, 2010 - 2017.

Names

Title: Infrared Spectra of Crystalline $C_2H_2$, $C_2HD$, and $C_2D_2$
Abstract: The infrared absorption spectra of polycrystalline films of $C_2H_2$, $C_2HD$, and $C_2D_2$ have been examined at 63K in the frequency range between 4500 and 450 cm$^-1$. The spectra of the solid state and the gas phase of the various acetylenes are compared and the appropriate vibrational assignments are made. Several absorptions attributable to combinations of lattice modes and molecular fundamentals were found. The observed multiplet structure of the fundamental vibrations indicates that in the low-temperature modification of $C_2H_2$ and $C_2D_2$ the molecules are located at sites of $C_2h$ symmetry. Spectra of various solid solutions composed of mixtures of isotopic species were obtained and their significance discussed. The effect of isotopic substitution on the splittings in the $ν_5$ region led to the conclusion that the dipole-dipole coupling model is sufficient to explain the observed spectra.
Keywords: spectroscopy, transmission spectra, band position, band vibration mode, mid-IR, molecular solid, C2H2, C2HD, C2D2
Content: spectral data, band list data, experimental physics

Doi

10.1063/1.1725436

Identifiers