Carbon molecules, spectroscopic constants

The molecule S12, like Se, is of Dsd symmetry but in the soHd state it occupies sites of the much lower C211 symmetry [163]. Due to the low solubihty and the thermal decomposition on melting only solid state vibrational spectra have been recorded [2,79]. However, from carbon disulfide the compound Si2-CS2 crystallizes in which the S12 molecules occupy sites of the high Sg symmetry which is close to 03a [163]. The spectroscopic investigation of this adduct has resulted in a revision [79] of the earher vibrational assignment [2] and therefore also of the earlier force constants calculation [164]. In Fig. 24 the low-temperature Raman spectra of S12 and Si2-CS2 are shown. 

The experimental methods presented in Part A permit us to determine the number of each type of carbon present in a molecule and the spatial relationships between protons, which are critical to the elucidation of the two- and, perhaps, three-dimensional structure of that molecule. As we have seen, this new information, combined with that obtained from chemical shifts, coupling constants, and other spectroscopic methods, might be sufficient to determine... 

This table gives selected values of the electric dipole moment for over 800 molecules. When available, values determined by microwave spectroscopy, molecular beam electric resonance, and other high-resolution spectroscopic techniques were selected. Otherwise, the values come from measurements of the dielectric constant in the gas phase or, if these do not exist, in the liquid phase. Entries are listed alphabetically compounds not containing carbon are listed first, followed by compounds containing carbon. 

Chedin, A. Carbon-dioxide molecule—potential, spectroscopic, and molecular constants from its infrared spectrum, J. Mol. Spectry. 1979, 76, 430-91. 

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