Showing papers in "Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy in 1978"

TL;DR: In this article, the CH stretching regions of both the Raman and i.r. spectra of the extended polymethylene chain have broad secondary maxima.

TL;DR: In this article, it was shown that a cluster of relatively narrow bands in the i.r. spectra in the range of 400-650 cm −1 can be correlated with the various BiO bonds in the highly distorted polyhedra that make up the bismuth-oxygen framework.

TL;DR: In this paper, the assignment based on group vibrational concept and isotopic shifts for most fundamental vibrations of all eleven isotopic species is proposed and discussed, and the comparison between in-phase and out-of-phase phenyl ring modes is made.

TL;DR: In this article, the normal coordinate analyses of hydrazine and d 4 have been performed employing both general valence and modified Urey-Bradley force fields, and the PED confirms the assignment of D urig et al. [1] for hydrazines but suggests revision of the assignment for the 938 cm −1 band of d 4.

TL;DR: Guanine, C-, N-, and completely deuterated analogues, and their 15N substituted derivatives on the pyramidic (N1, N2, N3) or imidazolic (N7, N9) part have been investigated by infrared and Raman spectroscopy in the polycrystalline state as mentioned in this paper.

TL;DR: In this paper, rather complete Raman and i.r. spectra of the two isotopic ions in aqueous solutions have been obtained and qualitatively interpreted and some revisions of previous assignments are suggested, based on the new data and the isotopic frequency shifts.

TL;DR: In this article, a conformational change from gauche to trans isomer occurs in the argon matrix due to the i.r. beam, supported by normal coordinate calculations.

TL;DR: In this paper, a normal coordinate analysis has been made for the optical active intra- and intermolecular vibrations of l -alanine crystal and the large factor group splittings observed for the CH3 asymmetric deformation and the CH 3 torsional modes were elucidated well by using the potential including only the non-bonded atom-atom repulsion interaction.

TL;DR: In this article, the anisotropy of the 31P chemical shift in solid phosphorus compounds with C3v symmetry and the PO bond length along the threefold axis are compared.

TL;DR: In this paper, the Raman active long wavelength phonons of an α Ga2S3 single crystal were studied at 300 and 7 K in the 2-800 cm−1 range.

TL;DR: In this paper, a valance force field constrained to a set of forty-three force constants by a number of clear-cut criteria has been derived, based on frequencies rather than frequency shifts in the case of all isotopic species.

TL;DR: In this paper, the i.r. spectra of 2-chloroethanol and its OD-deuterated analogue have been recorded in argon and nitrogen matrices and in the gas phase.

TL;DR: In this article, a vibrational assignment for each isotopic isomer is given for the point groups Cs and C3v, and the coupling between hydroxyl bending and a skeletal stretching vibration is discussed.

TL;DR: In this article, the ion pairs MNCS (M = Li, Na, K, Rb and Cs) and AgSCN have been studied in dimethylformamide solution (dimethylthioformamide for Ag SCN). Force constants have been calculated by using a solvated ion pair model.

TL;DR: In this article, the spectra of pyromorphite, vanadinite and mimetite have been recorded and normal coordinate analysis has been carried out for all frequencies observed.

TL;DR: In this paper, the authors measured the reflectance spectra of ten crystalline chromate salts and compared them with the spectrum of the chromate ion in solution, and found that the increase in the intensity of the 23,000 cm − 1 band in crystalline compounds can be explained by the increasing polarizing effect of the cations and the appearance of new low-energy bands in case of highly covalent metal.

TL;DR: The lattice vibrations of boehmite can be separated into O2− translations and OH− translations, lying between 300 and 410 cm−1 as discussed by the authors, and the true space group must be C122v (Cmc21), each domain of which probably extends over an entire hydrogen bonded double hydroxyl sheet.

TL;DR: The matrix isolation spectrum (in Ar at 20 K) of CrO 2 Cl 2 has been measured as mentioned in this paper, where exact force constants were obtained for the B 1 and B 2 as well as approximate ones for the A 1 species.

TL;DR: In this article, a halogen exchange of a highly diluted SCl2-rare gas mixture with AgF or HgF2 was used to produce sulfurdifluoride.

TL;DR: In this paper, the spectral data for heavy atom vibrations are consistent with C3v symmetry for isocyanate and isothiocyanates and there is good evidence for lower symmetry for the azide.

TL;DR: In this paper, the authors used the Ramaman spectra of 14 monosubstituted benzenes and eight p-deuterated derivatives to investigate the correlation between the CH out-of-plane deformation frequencies and the electronic properties of the substituent.

TL;DR: In this article, the infrared and Raman spectra of 1-Br-2,3-dimethyl benzene and 2-Br2,4-dimmethyl benzene were recorded using Perkin-Elmer (Model 621) double beam grating spectrophotometer and Argon ion laser respectively.

TL;DR: In this paper, the i.r. spectrum of benzene in matrices of Kr and Ar has been determined and shown to be strongly affected by aggregation of the benzene.

TL;DR: Using direct matrix diagonalization to solve the anharmonic Hamiltonian, the force field of Table 1 was found to provide a good fit for ClCN as mentioned in this paper, and the four known B 0 are fitted by the equilibrium distances r e (ClC) = 162.995 pm and r e(CN) = 115.923 pm.

TL;DR: In this article, it was shown that the ratio between the frequencies of corresponding bands in pyridine-d5 and Pyridine lies within the range 0.95 ± 0.05 (ring vibrations) or 0.75 ± 0.03 (CH vibrations).

TL;DR: Inverse polynomials of the type y = a (1 + bx 2 + cx 3 + dx 4 ) −1 prove to be very convenient and, unlike truncated moments and log/log plots of band shapes, do not require the location of an accurate experimental baseline.

TL;DR: In this article, the infrared and Raman spectra of the β phase of H 2 C 2 O 4, H 2C 2 18 O 4 and D 2 C O 4 were investigated at various temperatures (300-30 K) in the 4000-50 cm − range.

TL;DR: In this paper, a simple bent M←OL vibrational model has been used to estimate from ν (MO) and ν(SO) the force constants FMO and FOL for some O-bonded DMSO (dimethylsulfoxide), TMSO-d6 and TMTM (tetramethylenesulfoxide) complexes, and is used to aid the assignment of the i.r. spectra of a series of lanthanide(III)-DMSO complexes.

TL;DR: In this article, the electronic spectrum at room temperature of perylene below 46 kcm −1 was divided into two component spectra polarizing to the long ( x ) and short ( y ) axes of the molecule.

TL;DR: In this paper, the absorption, reflection, and Raman spectra of single crystals of KD-malonate at room and liquid N 2 temperatures were obtained. And from the present data combined with previous results obtained with acid salts of carboxylic acids of different crystal symmetry conclusions are drawn which concern spectral features connected with hydrogen bonding, in particular the strong absorption near 1000 cm −1 and the bands in the carbonyl region.