摘要:

AbstractThe Raman spectrum of liquid trifluoromethylthiosulphenyl chloride and its IR spectra in the vapour and solid phases in neon and argon matrices were recorded. Polarized Raman spectra of liquid trifluoromethylthiosulphenyl chloride suggestC1symmetry. Assignment of 14 of the 15 fundamental vibrations is carried out. A correlation between the S‐‐S stretching wavenumber and the sum of the group electronegativities of the disulphan substituents is proposed.The valence force constants were calculated by semi‐empirical methods and the values obtained compare favourably with results from previous calculations on related comp

ISSN:0377-0486    

DOI:10.1002/jrs.1250200502

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractThe temperature‐dependent Raman spectra of crystalline uranyl nitrate hexahydrate, UO2(NO3)2· 6H2O, are reported in the temperature range 15‐290 K. A group theoretically consistent assignment of the bands in terms of UO 22+, NO3−and H2O vibrations is proposed. The temperature‐dependent studies of thermosensitive bands associated with these entities were used to study the previously reported phase transition at 140 ± 5 K and to detect another phase transition at 190 ± 5 K. The latter transition shows up prominently in the temperature‐dependent fluorescence studies and is also accompanied by a sharp increase in the Rayleigh scattering. The transition at 190 ± 5 K is triggered by the dynamics of H2O‐II and UO 22+whereas that at 140 ± 5 K is associated with the dynamics of H2O‐II/NO3−. Both the transit

ISSN:0377-0486    

DOI:10.1002/jrs.1250200503

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractAn experimental study of the Raman intensities of cyclohexane in the gas phase is presented. The absolute scattering coefficients and depolarization ratios corresponding to clearly differentiated spectral regions (containing one or more normal modes) were measured. The absoulute intensity of the 802 cm−1Raman line was used as an external intensity standard. The value ofSobtained for this band is 12.24 × 10−81C2V

ISSN:0377-0486    

DOI:10.1002/jrs.1250200504

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractThe GF matrix method has been applied to the analysis of the aromatic ring and the benzene molecule. A normal coordinate treatment based on the local symmetry force field was performed. A set of the elements of theFmatrix was obtained that gives vibrational frequencies of these molecules in agreement with the observed values.

ISSN:0377-0486    

DOI:10.1002/jrs.1250200505

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractPrevious resonance Raman studies with the spinning cell technique indicated that the L550intermediate gave a doublet at 1552 and 1539 cm−1for the CC stretching mode whereas the results from the flow cell technique suggested that the two bands arise from different intermediates on the basis of different kinetic behaviour. This study has explored the origin of the discrepancy by applying both the double‐beam flow apparatus and the spinning cell to an identically prepared sample for observing transient resonance Raman spectra. It was found that the presence of a very small amount of dark adapted species caused the apparent differences in the kinetic behaviour of these two

ISSN:0377-0486    

DOI:10.1002/jrs.1250200506

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractThe Raman spectrum of methyl iodide was recorded in the 3000 cm−1region with a resolution of 0.25 cm−1. The range measured includes the ν1, ν4bands of symmetry speciesA1andE, respectively. Using published vibrational–rotational constants, a computer simulation of the band contour was carried out, yielding relative values of Raman polarizability derivatives for these bands. Further, from previous measurements of the scattering cross‐section the moduli of the Raman tensor components related to ν1and ν4vibrational modes were

ISSN:0377-0486    

DOI:10.1002/jrs.1250200507

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractThe Raman (3500–10 cm−1) and infrared (3500–50 cm−1) spectra of gaseous and solidn‐propylamine, CH3CH2CH2NH2, and its deuterated analog, CH3CH2CH2ND2, were recorded. Additionally, the Raman spectra of the liquids were measured and qualitative depolarization values were obtained. From the fact that several distinct Raman lines disappear on goning from the fluid phases to the solid state, it is concluded that the molecule exists as a mixture of several conformers, with thetrans–transconformer being the most stable form in the solid. The first term indicates the position of the methyl group relative to the CN bond, whereas the second term indicates the position of the lone electron pair on the nitrogen relative to the central CC bond. Relying mainly on group frequencies, depolarization data and relative intensities of Raman and infrared bands, a complete vibrational assignment is proposed for thetrans–transconformer.Ab initiocalculations were carried out on these molecules, employing both 3–21G and 6–31G* basis sets. The results obtained using these basis sets are compared, and used in normal coordinate calculations. The results of theab initiocalculations support the vibrational assignment, and also indicate that it is thetrans–transandtrans–gaucheconformers which are the more stable forms ofn–propylamine and hav

ISSN:0377-0486    

DOI:10.1002/jrs.1250200508

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractThe characteristics of hyper‐Raman scattering employing circularly polarized incident radiation were studied using Cartesian tensor methods. Expression for the reversal factor,P(θ), and circularity,RC(θ), and their relationship with the depolarization factors, ρ⊥and ρn, have been derived. An analysis of hyper‐Raman spectrum of a molecule withD3hsymmetry is

ISSN:0377-0486    

DOI:10.1002/jrs.1250200509

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractThe Raman spectral bandshapes of the ν1(A1), ν3(A1) and ν4(E) vibrations of CH3I were studied as a function of temperature in the liquid phase. Perpendicular diffusion coefficients calculated from ν3agreed well with earlier reported results. The degenerate CH3stretching vibration, ν4, was analyzed via fitting by a model incorporating two Lorentzian lineshapes. Values of the parallel diffusion constants,D∥, determined using only the narrower component were in excellent semi‐quantitative agreement with those predicted by the free rotor model of molecular reorientation. Analysis of the room‐temperatur Raman spectrum of ν5(E) yielded the same value ofD∥as that calculated from ν4. The room‐temperature infrared spectral intensities of ν5were fitted by a model with a narrow Lorentzian containing contributions from rotational and vibrational relaxation superposed on a second component introduced to account for the broad background absorption.D∥determined from the IR bandwidth was in good agreement with values obtained from the Raman spectra of ν4and ν5. These results demonstrate the utility of analyzing degenerate vibrational modes to determine the parallel diffusion coeffi

ISSN:0377-0486    

DOI:10.1002/jrs.1250200510

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

ISSN:0377-0486    

DOI:10.1002/jrs.1250200501

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY