High-resolution Fourier-transform infrared spectroscopy of ν3+ν8 H2CCS, ν1 HDCCS and ν1 D2CCS in the gas phase: an improved rS structure for thioketene

Abstract

The ν₃+ν₈ combination band of H₂CCS and the C—D ν₁ stretching fundamentals of HDCCS and D₂CCS in the gas phase have been investigated by high-resolution FTIR spectroscopy. All upper vibrational levels were perturbed. This investigation has yielded accurate values for the ground-state A rotational constant for all three isotopomers and this has enabled the positions of the hydrogen nuclei to be precisely fixed in an r_s structure. In addition, the fundamental frequencies for all three isotopomers from both low- and high-resolution spectra are presented.