Vibrational spectra of polyacetylenic compounds

Force fields are determined for diacetylene and dimethyldiacetylene. It is concluded that -electron density is displaced from the triple bonds to the single one in the butadiyne system. Characteristic features of the force fields of conjugated organic molecules are presented. The vibrational spectra of polyacetylenes are examined. It is shown that increase in chain length does not lead to equalization of the orders of the triple and single bonds. It is concluded that the intramolecular effects of substituents die out rapidly along the chain.Zhurnal Prikladnoi Spektroskopii, Vol. 5, No. 4, pp. 498–505, 1966     

Vibrational spectra of ternary ordered vacancy compounds

We have studied the lattice dynamics of A²B ₂ ³ C ₄ ⁵ crystals with the thiogallate structure using a nonpolarized ion model. We computed the interatomic interaction parameters for nine compounds. The calculated phonon spectra, density of vibrational states, and temperature dependence of the specific heats agree well with the available experimental data. V. D. Kuznetsov Siberian Physicotechnical Institute, Tomsk University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 85–89, February, 1998.     

Vibrational spectra of nitrogen-containing six-membered heterocyclic compounds

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 48, No. 3, pp. 414–420, March, 1988.     

Vibrational spectra of LiRbSO4

The IR and Raman spectra of LiRbSO₄ have been recorded and analysed on the basis of vibrations of the SO^2-₄ ion. The splitting of the non-degenerate symmetric stretching mode of the SO^2-₄ ion into three components in Raman suggests the possibility of resonance interaction between SO^2-₄ ions in the unit cell. The linear distortion of the SO₄ tetrahedra seems to be greater than the angular distortion.     

Vibrational spectra of benzophenone conformers

We have used direct quantum DFT methods to calculate the parameters of the adiabatic potential of four benzophenone conformers. According to the data obtained, the existence of only one conformer is possible (C₁ symmetry) for the free benzophenone molecule, for which torsional vibrations of the benzene moieties are reproduced and for which we calculated the vibrational spectrum in the anharmonic approximation of the theory of molecular vibrations. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 5, pp. 561–564, September–October, 2007.     

Vibrational spectra of 1,3,5-trichlorotrifluorobenzene

Infrared (4000-80 cm^?1) and Raman spectra of a highly purified sample of 1,3,5-trichlorotrifluorobenzene in the solid, solution, and vapor states have been measured. Assignments of all the fundamental frequencies are made, completed by the use of calorimetric data.     

Vibrational spectra of 2-furaldehyde

The infrared spectra of 2-furaldehyde and its deutero analog were measured in the gaseous and liquid states and in solutions. The band contours of the spectra of the gaseous phase were discussed. Normal coordinate calculations were carried out and related to the band assignment.     

Vibrational spectra of monosubstituted acetylenes

The frequencies and envelopes (modes) of the normal vibrations of the molecules CH₃CCH, FCCH, BrCCH, and ICCH have been calculated and their force constants determined.     

Vibrational spectra of 2-oxo-pyrrolidineacetamide

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 53, No. 6, pp. 944–950, December, 1990.     

Vibrational spectra of fluorohafnate glass

We report the first detailed measurements of fundamental vibrational spectra in fluorohafnate glass. The Raman spectrum is dominated by a single relatively broad peak in the vicinity of 570–590 cm^?1 attributed to Hf-F stretching modes, while the infrared spectrum displays two prominent broad peaks. The location of the high frequency peaks is shown to be consistent with the observed position of the infrared absorption edge.     

Vibrational spectra and structure of polyene compounds. II. Band intensity in the vibrational spectra of linear polyenes

Analysis of infrared intensities shows that a polyene molecule has a system of conjugated and polar carbon bonds. The most intense bands in the Raman spectra are connected with vibrations involving the whole chain and a maximum change in the polarizability.