ISSN:0005-9021    

DOI:10.1002/bbpc.19810850602

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1981

数据来源: WILEY

摘要:

AbstractThe present paper gives a survey over applications of vibrational spectroscopy — especially RAMAN methods — in inorganic chemistry. The following topics are covered: analytical application for the characterisation of molecular compounds, their symmetry and structure, discussion of bond properties by means of Valence Force Field methods, effects of intermolecular interactions on the spectra of liquids and solids. The importance of intensity calculations for the check and improvement of force field calculations is briefly referred to. These different aspects of RAMAN spectroscopy are introduced using examples from recent literature and from the current work of the aut

ISSN:0005-9021    

DOI:10.1002/bbpc.19810850603

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1981

数据来源: WILEY

摘要:

AbstractThe enhancement of Raman scattering for pyridine molecules on Au, Ag, and Cu and for water and halide ions on Ag and Cu electrodes has been investigated. — An enhancement has been found only in that spectral region where relative undamped surface plasmon polaritons (SPP) can be excited, showing a general increase for long wavelength excitation. — The electrochemical pretreatment of the metal surfaces. consisting in an oxidation/reduction cycle creates large scale roughness and adatom‐adsorbate complexes, both of which are necessary simultaneously in order to obtain intense SER scattering. — It is infered that the enhancement results from high density of SPP quanta created at rough or particularly shaped metal surfaces and the SPP scattering cross section being significant larger than that of

ISSN:0005-9021    

DOI:10.1002/bbpc.19810850604

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1981

数据来源: WILEY

摘要:

AbstractIn this paper a theory is presented for calculating the resonant Raman intensities for all 3N‐6molecular vibrations of a molecule excited by a Π → Π* electronic transition using only the known geometry of the molecule, the force constants (i. e. force field) for the internal coordinates and a molecular orbital calculation of all of the C‐ C and C‐ N bond orders in the ground and excited electronic states. Criteria are presented for the refining of a force field on the basis of observed and calculated resonant Raman intensities. — The method has been applied to 1‐methyl uracil. excited states which occur at 260 nm and 190 nm. The calculated intensities are compared with measured resonant Raman intensities using exciting light at 266 nm, 257 nm, and 212.8 nm. The agreement is satisfactory in that only the observed resonant Raman bands are calculated to h

ISSN:0005-9021    

DOI:10.1002/bbpc.19810850605

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1981

数据来源: WILEY

摘要:

AbstractResonance Raman (RR) spectra were obtained from aqueous suspensions of the purple membrane of Halobacteria. The RR spectra reflect the photolabile retinal chromophore of bacteriorhodopsin which induces proton translocation across the membrane. RR spectra of the all‐trans chromophore BR570and its 13‐cis component BR548were recorded both in H2O and D2O suspension. The vibrational analysis revealed characteristic hydrogen bending modes of the Schiff base linkage by which retinal is bound to the protein. These bands are very sensitive to structural changes of the Schiff base and allow conclusions on geometrical and electronic changes of this group which play an important role in the proton translocation proc

ISSN:0005-9021    

DOI:10.1002/bbpc.19810850606

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1981

数据来源: WILEY

ISSN:0005-9021    

DOI:10.1002/bbpc.19810850607

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1981

数据来源: WILEY

ISSN:0005-9021    

DOI:10.1002/bbpc.19810850608

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1981

数据来源: WILEY

摘要:

AbstractThe line shape of Raman bands and its relation to rotational and vibrational relaxation is the topic of the present contribution. First, rotational and vibrational correlation functions are introduced. Depending on the vibrational mode under study the rotational correlation functions contain information on rotations about different molecular axes. The discussion will be restricted to linear and symmetric top molecules, for the first of which “tumbling” and the latter “tumbling” and “spinning” reorientational motions are of importance. Experimental correlation functions for CO2, CH3J, and CH3CN of totally symmetric and degenerate bands are discussed. A comparison of the experimental correlation functions with those obtained from the rotationalJ‐diffusion model will be given. — Next, vibrational relaxation (dephasing) is considered. Several mechanisms may contribute to vibrational dephasing. The popular Kubo‐model for vibrational relaxation is introduced and the relaxation of thev2‐band of CH3J is discussed in terms of this model. — The paper closes with a brief discussion of interaction induced scattering. Interaction induced scattering contributes to the wings of depolarised Rayleigh (pure rotational Raman) and Raman scattering and therefore is a severe source of error for the short time behaviour of rotational and vibrational correlation functions. Different approaches to correct experimental s

ISSN:0005-9021    

DOI:10.1002/bbpc.19810850609

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1981

数据来源: WILEY

摘要:

AbstractThe dependence of the surface enhanced Raman signal of CN−ions on silver/electrolyte interfaces at 2114 cm−1on the electrode potential was investigated by a periodic pulse program allowing the registration of the time dependence. The results can be interpreted by concentration changes in the diffusion region in front of the electrode as well as by reorganization processes of silver deposits on the electrode surf

ISSN:0005-9021    

DOI:10.1002/bbpc.19810850610

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1981

数据来源: WILEY

摘要:

AbstractRaman spectra of the mercurimethanes C (HgX)4(X = Cl, Br, and I), CH (HgCl)3, and CH2(HgX)2(X = Cl and Br) at high pressures up to about 6 GPa were studied.v(CH) andv(CHg) valence vibrations show strong and medium pressure dependences in the ranges (13.8 ± 2.7) and (7.6 ± 1.7) cm−1· GPa−1, respectively. It is concluded that obviously anharmonic vibrations of light atoms with large vibrational amplitudes should exhibit high pressure sensiti

ISSN:0005-9021    

DOI:10.1002/bbpc.19810850611

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1981

数据来源: WILEY