摘要:

AbstractThe Raman activeT2gmode was observed in the optical absorption spectrum obtained by the Fourier transform spectroscopic technique in an undoped single crystal of Cdln2S4. This was activated owing to the partially inverse spinel structure of Cdln2S4. It is quite possible that infrared modes can also be activated for the Raman process and hence data obtained with Raman spectroscopy should be re‐examine

ISSN:0377-0486    

DOI:10.1002/jrs.1250130302

出版商:John Wiley&Sons, Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractThe Raman spectra of KHSO4single crystals in different geometries have been investigated in the 10–4000 cm−1range at 300 K, 150 K and 120 K. The infrared spectra of polycrystalline KHSO4have also been measured. An interpretation of these results consistent with the crystal structure and other information on this system is presen

ISSN:0377-0486    

DOI:10.1002/jrs.1250130303

出版商:John Wiley&Sons, Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractL'acide pivalique (TMAA) se présente sous forme de dimères par double liaison hydrogéne. Un calcul en coordonnées normales est mené pour les quatre isotopesd0,d1,d9etd10.L'affinement conduit à 45 constantes de force et à la description détaillée de l'ensemble des mouvements. Une visualisation est donnée pour certains mouvements caractéristiques (notamment du cycle) et plus particulièrement en basse fréquence (torsions). Les valeurs des barrières de potentiel sont données pour les torsions des groupements m

ISSN:0377-0486    

DOI:10.1002/jrs.1250130304

出版商:John Wiley&Sons, Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractL'examen comparatif des spectres infrarouges et Raman d'une série d'alcools β‐cyclopropylidéniques et de certains de leurs homologues deutériés permet de proposer une attribution des principales vibrations fondamentales. Les résultats montrent qu'il existe des bandes de vibration pouvant être utilisées pour caractériser la classe d'alcool, le groupement cyclopropylidénique et le degré de substitution en posit

ISSN:0377-0486    

DOI:10.1002/jrs.1250130305

出版商:John Wiley&Sons, Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractSince the carbonyl stretching modes of membrane phospholipids reflect molecular perturbations and reorganizations at the bilayer interface region, a definitive assignment is desired of the vibrations associated with the carbonyl transitions at either thesn‐1orsn‐2lipid chain position. Ether glycerol phospholipids containing one alkyl ether chain and one acyl chain, with the carbonyl group in either thesn‐1orsn‐2chain, provide lipid systems for establishing these assignments. rac‐1‐0‐Hexadecyl‐2‐palmitoyl‐sn‐glycero‐3‐phosphorylcholine yields a carbonyl stretching mode at 1716 cm−1, while the carbonyl mode for 1‐palmitoyl‐2‐0‐hexadecyl‐sn‐glycero‐3‐phosphorylcholine shifts to 1737 cm−1, By eliminating thegauchebond at the α‐carbon position of thesn‐2acyl chain in 1‐0‐hexadecyl‐2‐acetoyl‐sn‐glycero‐3‐phosphorylcholine, the lower frequency carbonyl fundamental reverts to a higher frequency (1739 cm−1) characteristic o

ISSN:0377-0486    

DOI:10.1002/jrs.1250130306

出版商:John Wiley&Sons, Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractRaman and infrared spectra (5‐2000 cm−1) of Cr(CO)3(η6‐C6H6), Mo(CO)3(η6‐C6H6) and W (CO)3(η6‐C6H6) and of the deuterated derivatives (d6) of the Cr and Mo complexes have been recorded in the 5‐300 K temperature range. The low frequency region has been extensively studled. New modes are identified and a new assignment in this region is proposed. The temperature dependence of the low frequency spectra is discussed in connection with recent quasielastic neutron scattering results. Broadenings of the Raman bands are interpreted in terms of anharmonicity and vibrational dephasing connected with large amplitude motions associated with a potential barrier of 4.7 kcal mol−1, A qualitatlve representation of the potential driving the torsional motion is proposed and it is pointed out that the intermolecular potential plays a dominant role. 2π/6 ring jumps involving an activation energy of 3.9 kcal mol−1, as deduced from neutron scattering in Cr(CO)3(η6‐C6H6), occur, but the proportion of molecules in the state of jump is only 0.3% at 300 K and therefore the rate of dynamic disorder is too low to induce an order‐disorder phase transition. This result is consistent with our c

ISSN:0377-0486    

DOI:10.1002/jrs.1250130307

出版商:John Wiley&Sons, Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractThe influence of hydrostatic pressure on lattice vibrations in single‐crystals ofd0‐ andd8‐naphthalene has been measured by observations of their first‐order Raman scattering spectra at pressures in the range 0‐8.5 kbar. Measurements were performed at room temperature for both the external and the internal vibrations. Mode Grüneisen parameters γiin the range 3‐4.5 and 0.004‐0.25 have been derived for external and internal mode

ISSN:0377-0486    

DOI:10.1002/jrs.1250130308

出版商:John Wiley&Sons, Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractThe vibrational spectra of NaOX (X = H or D) at room temperature and 77 K are reported. A normal co‐ordinate analysis has been carried out to assign the observed bands on the basis of the valence force field. The force constants were adjusted by considering a bond distance and reproduce well the observed frequencies. In the dispersion relations on k2and kxthe librational modes were found to be insensitive to k, whereas the translational modes except for theA1gandB1umodes vary considerably with k. Some bands were assigned to the combination band between a fundamental and an acoustic mod

ISSN:0377-0486    

DOI:10.1002/jrs.1250130309

出版商:John Wiley&Sons, Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractThe ν1band of natural germane (GeH4) has been recorded using a continuous wave stimulated Raman experiment which we describe in this paper. The resolution is about 0.005 cm−1at 10 Torr pressure. In the first stage of the analysis, the Raman lines were identified thanks to the recent study of the ν1and ν3bands made by Lepage, Champion and Robiette. In the second stage, the stimulated Raman data were combined with the infrared data to refine the excited state constants of the isotopic species70GeH4,72GeH4and74

ISSN:0377-0486    

DOI:10.1002/jrs.1250130310

出版商:John Wiley&Sons, Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractLes cristaux BeSO4, 4H2O et BeSO4, 4D2O étudiés par diffusion Raman (4000 à 4 cm−1) montrent tous deux des éclatements TO‐LO qui confirment leur structure à caractère piezoélectrique. Des modes obliques distincts montrent un caractére mixteB2etE.Des charges dynamiques effectives ont été calculées. Un effet électrooptique a ét

ISSN:0377-0486    

DOI:10.1002/jrs.1250130311

出版商:John Wiley&Sons, Ltd.    

年代:1982

数据来源: WILEY