bluuebunny/crossref_metadata_2025_split huggingface dataset:
Raman tensors for planar and pyramidal AB3 molecules
Authors: Bródka A. , Stryczek B. 
Published: May 2005

AbstractOn the basis of bond polarizability model, expressions for second derivatives of the polarizability tensor with respect to the normal coordinates of planar and pyramidal AB3 molecules are presented. Using the results obtained, the relationship between the first and the second derivatives of the mean polarizability is found.
Resonance Raman analysis of astaxanthin–protein complexes
Authors: Merlin Jean Claude 
Published: May 2005

AbstractA survey of resonance Raman spectra of carotenoproteins, including astaxanthin, is presented. The data are discussed and compared with absorption measurements in order to establish the mode of binding. Three mechanisms seem to be dominant in explaining the changes which occur in the resonance Raman and absorption spectra of astaxanthin. The polarization of the π‐electron system is responsible for the large red shift in the absorption λmax and the decrease in the CC stretching wavenumber. A distortion of the backbone plane involving double bonds can produce an increase of the CC stretching wavenumber and a red shift of the absorption band. Effects of the medium on excited states can produce red or blue shifts of the absorption band without perturbation of the ground electronic state properties. The interference of these mechanisms can explain the observed changes in the resonance Raman spectrum of astaxanthin bound to proteins and the great diversity of the results.
Laser Raman and infrared spectra of Rochelle salt crystals
Authors: Bhattacharjee R. , Jain Y. S. , Raghubanshi G. , Bist H. D. 
Published: May 2005

AbstractA systematic analysis of the IR and Raman spectra of Rochelle salt (NaKC4H4O6 · 4H2O) in terms of the standard frequency correlations, deuteration shift and typical nature (with respect to intensity and width) of bands due to different modes is reported. The bands due to the internal modes (excluding some skeletal modes) of the C4H4O ion appear as doublets. For certain modes [e.g. βCH, νC(OH) and δCOO] doublets arise owing to interactions between two identical oscillations of two identical groups in COO(HO)HCCH(OH)COO2−, while for other modes (e.g. νCH, ν, ν, δCOH and τCOO) they arise owing to crystallographically distinguishable sites for two identical oscillators.
Raman intensities of liquids: Precise relative measurement of some potential secondary standards, and an interim scale of absolute intensities for blue and green excitations
Authors: Eysel Hans H. , Bertie John E. 
Published: May 2005

AbstractThe spinning divided Raman liquid cell has been used to measure the relative integrated Raman intensities of several bands of C6H6(I), CCI4(I), C6H12(I), C6D6(I), CH3CN(I), CH2CI2(I), SO(aq.), and CIO4 −(aq.) at room temperature. To convert these relative intensities to absolute scattering activities, the average of the eight literature values of the absolute Raman scattering cross‐section of the 992 cm−1 band of C6H6(I) under blue or green excitation was used. This yielded an unpolarized scattering activity per molecule of 640 ×10−9 cm4 g−1, with a standard deviation of 80 ×10−9 cm4 g−1 [in SI units, 792 ×10−34 and standard deviation 100 ×10−34 (C m2/V)2/(m2 kg)]. It is suggested that this value can be used as the basis for an interim scale of Raman scattering intensities. The scattering activities on this scale are higher than those in the literature because the benzene calibration value is higher than has been used previously. The relative scattering activities obtained agree well with those of Nestor and Lippincott. It is suggested that fairly weak and depolarized bands are often better secondary standards for relative intensity measurements than the very strong, very polarized bands that have traditionally been used.
Raman and far‐infrared study of the polar single crystals of 3‐(4‐chlorophenyl)‐2‐cyanopropenonitrile
Authors: Bugueno‐Hoffmann Rosa , Romain François , Pasquier Bernadette 
Published: May 2005

AbstractLow‐frequency Raman and infrared spectra of a single crystal of 3‐(4‐chlorophenyl)‐2‐cyanopropenonitrile have been obtained and an assignment of the bands to their symmetry species has been made. Normal coordinate calculations using a dynamic lattice model with only a short‐range atom‐atom potential confirm roughly the experimental assignments but suggest the need to introduce an electrostatic potential in the lattice mode calculation of this polar crystal. Polarized infrared reflection spectra have been studied in order to determine the longitudinal and transverse optical frequencies, damping factors, oscillator strengths and induced dipole moments of the optical phonons. Approximate dynamic charges on the CN groups and on the whole molecule were estimated.
Resonance Raman and infrared spectra of the Pr(PAN)3 complex
Authors: Drożdżewski Piotr M. 
Published: May 2005

AbstractThe complex of praseodymium with 1‐(2‐pyridylazo)‐2‐naphthol (HPAN) has been investigated by resonance Raman and IR spectroscopy. It has been found that the Pr(PAN)3 complex exhibits tautomerism in various organic solvents. The excitation profiles of the observed Raman bands have been obtained and used for vibrational band assignments.
Optical spectroscopic studies of the polymorphic forms of 1, 4‐dihydroxyanthraquinone
Authors: Dutta Prabir K. , Lee B. S. 
Published: May 2005

AbstractElectronic, infrared and resonance Raman spectra of the two crystalline polymorphic forms of 1, 4‐dihydroxyanthraquinone are reported. The differences in the spectral properties are explained on the basis of the intermolecular hydrogen bonds in one form compared with intramolecular hydrogen bonds in the other form. The intermolecular interaction leads to exciton splitting and strong hypochromic effects in the resonance Raman spectrum. The optical properties of the intramolecular hydrogen bonded form resemble that of the anthracycline drug adriamycin and serves as a useful model.
Detection of calcific deposits in atherosclerotic lesions by laser Raman spectroscopy
Authors: Clarke R. H. , Hanlon E. B. , Brody H. , Isner J. M. 
Published: May 2005

AbstractThe laser Raman scattering from calcified regions of diseased cardiovascular tissue samples dissected from the coronary arteries and aortic valves was measured. The spectra reveal the characteristic vibrational features of the phosphate grouping in the solid state. Spectral features for the calcified artery segments and aortic valves are compared for details of the chemical and structural makeup of the calcific lesions.
Raman spectra and binding of CuII to purine nucleotides
Authors: Carmona P. , Huong P. V. , Gredilla E. 
Published: May 2005

AbstractRaman spectra of adenosine 5′‐monophosphate, poly(rA), guanosine 5′‐monophosphate and their CuII complexes have been obtained and analysed by referring to spectra of D‐, 15N‐ and 13C‐labelled nucleobases. The greatest spectral changes on attachment of CuII to these nucleotides are associated with changes in the five‐membered ring and suggest that the metal binds preferentially to N‐7 of nucleobases. However, in the CuII coordinated poly(rA) species, N‐1 binding sites are also present to some extent, as deduced from the comparison of the Raman spectrum of the Cu‐poly(rA) complex with that of the protonated polynucleotide. In the complexes of guanosine 5′‐monophosphate with CuII, the guanine residue is located at the anti position with respect to the ribose moiety through the glycosidic bond. In all cases, strong changes are also recorded for characteristic bands of phosphate groups, indicating their participation as ligands surrounding CuII.
Dunham coefficients of 14N2 from CARS measurements of high vibrational states in a low‐pressure discharge
Authors: Lavorel B. , Millot G. , Lefebvre M. , Péalat M. 
Published: May 2005

AbstractSpectroscopic constants of the X 1Σg+ ground state of 14N2 are deduced from CARS spectra recorded in a 4 Torr d.c. N2 glow discharge. Vibrational states up to ν = 14 have been observed but only the 11 lower levels which have a good signal‐to‐noise ratio have been processed. The Dunham constants that were deduced yield vibrational band centre positions in good agreement with those of Lofthus and Krupenie.
Raman and force‐field studies of potassium tetrabromoindate in the solid state
Authors: Lorriaux‐Rubbens A. , Wallart F. , Wignacourt J. P. 
Published: May 2005

AbstractRaman spectra of a single crystal of KInBr4(space groupPnna) have been recorded in the temperature range 298–80 K and assigned. The overlapping of bands due to fundamentals and lattice modes leads to some complexity in these results. A force‐field calculation has been made to complete the interpretation.
Raman and infrared spectra of some aromatic amine–sulphur dioxide molecular complexes
Authors: Faria D. L. A. , Santos P. S. 
Published: May 2005

AbstractThe Raman and infrared spectra of the molecular complexes formed by sulphur dioxide and aniline, N‐methylaniline (NMA), N, N‐dimethylaniline (DMA), N, N‐diethylaniline (DEA), p‐phenylenediamine (PPD) and N, N, N′,N′ ‐tetramethyl‐p‐phenylenediamine (TPD) were obtained. With NMA, DMA and DEA only minor changes were observed in the vibrational frequencies of the amines and the SO2 vibrational shifts show that the complexes are considerably weaker than the well known trimethylamine‐sulphur dioxide complex. On the other hand, with PPD and TPD there are significant variations in the spectra of the amines on complexation and the shifts of the SO2 vibrational frequencies show that the interaction is comparable in strength to that existing in the trimethylamine‐sulphur dioxide complex. In the aniline‐sulphur dioxide complex the spectral data reveal strong intermolecular hydrogen bonding interactions.The pre‐resonance enhancement observed for the DMA and TPD complexes confirms the participation of the SO2 moiety in the chromophoric group and adds evidence for the change‐transfer nature of the interaction.
Raman spectroscopy of L‐tryptophan‐containing peptides adsorbed on a silver surface
Authors: Lee Hong In , Suh Se Won , Kim Myung Soo 
Published: May 2005

AbstractSurfac‐enhanced Raman spectra of L‐tryptophanylglycine (L‐Trp‐Gly) and L‐tryptophanylglycylglycine (L ‐Trp‐Gly‐Gly) adsorbed on a silver surface were obtained. More detailed investigations than in a previous study on the surface‐enhanced Raman scattering from L‐tryptophan (L‐ Trp) and glycyl‐L‐tryptophan (Gly‐L‐Trp) were also made. It was found that L‐Trp and the above peptides adsorb on the silver surface via both the carboxylate (COO−) and the amino (NH2) groups. Interestingly, the nitrogen atom of the indole ring of L‐Trp was found to bind to the surface only when L‐Trp is the C‐terminal residue.
Raman intensities of phosphate and diphosphate ions in aqueous solution
Authors: Eysel Hans H. , Lim Kye Taek 
Published: May 2005

AbstractThe Raman intensity spectra of potassium phosphate and diphosphate in aqueous solution have been measured against perchlorate solution as an external standard. Including the intensities of triphosphate, proportionality was found between the total trace scattering, which covers the PO stretch frequencies only, and the number of PO bonds. The force field for PO was revised according to the requirement of the intensity ratio of ν3 and ν4. A tentative force field for P2O was calculated. Based on these normal coordinate analyses, the electro‐optical parameters of PO bonds in phosphate and pyrophosphate are given.
A low‐temperature bulk electrolysis cell for in situ resonance Raman spectroelectrochemistry: Observation of the FeIVO stretching frequency for electrogenerated ferryl tetramesitylporphyrin
Authors: Czernuszewicz Roman S. , Macor Kathleen A. 
Published: May 2005

AbstractA simple, small‐volume, low‐temperature bulk electrolysis Raman spectroelectrochemical cell has been constructed which allows collection of resonance Raman (RR) spectra in situ from a rapidly stirred electrolysed solution. The cell has been used to obtain the first RR spectrum of electrochemically generated ferryl tetramesitylporphyrin (TMPFeIV O), formed at −40°C by electrooxidation of TMPFeIIIOH in CH2CI2 solution.
Raman spectra of the NaH2PO4 crystal
Authors: Choi B. K. , Lee M. N. , Kim J. J. 
Published: May 2005

AbstractRoom‐temperature and low‐temperature (10 K) Raman spectra of a single crystal NaH2PO4 were obtained for various polarizations. The polarization characteristics of the Raman spectra remained unchanged throughout the whole temperature range studied. This confirms that there is no phase transition in this crystal at least down to 10 K. High‐frequency H modes showed the well known ABC‐type three‐band structure and correlated with OH…︁O bond length.
Vibrational spectra of pyrazincarbonitrile and [15N]pyrazincarbonitrile
Authors: Delgado M. J. Martin , Márquez F. , Suero M. I. , Marcos J. I. 
Published: May 2005

AbstractPyrazinecarbonitrile and its 15N isotopic derivative were synthesized with an isotopic content of 99.4% and then Raman and infrared spectra recorded and assigned on the basis of isotopic shifts and depolarization ratios. The geometry in an MNDO approximation was also optimized.
Raman single crystal studies of spinel type MCr2S4(M  Mn, Fe, Co, Zn, Cd), MIn2S4(M  Mn, Fe, Co, Ni), MnCr2–2xIn2xS4 and Co1‐xCdxCr2S4
Authors: Lutz H. D. , Becker W. , Müller B. , Jung M. 
Published: May 2005

AbstractThe Raman spectra of single crystals (grown by chemical vapour transport with I2, AlCl3, CrCl3 and InCl3 as transporting agents) and polycrystalline samples of spinel type MCr2S4 (M  Mn, Fe, Co, Zn, Cd), MIn2S4 (M  Mn, Fe, Co, Ni), MnCr2–2xIn2xS4 and Co1–xCdxCr2S4 were recorded. The main results obtained are (i) large resonance enhancement effects, (ii) breakdown of the translation symmetry in inverse spine (MIn2S4), which results in band broadening and the observation of more bands than group theoretically allowed, e.g. a clustering mode (A1g) at about 250 cm−1, (iii) two‐mode behaviour of the breathing modes of the tetrahedral MS4 units (A1g) in both spinel solid solutions and partly inverse ternary spinels and (iv) frequency shifts of the observed bands caused by the tetrahedrally coordinated metal ions due to mass effects (F2g modes) and both bonding (ionic charge, covalency) and repulsion interactions (A1g modes).
Spectroscopic studies on trifluoroacetyl iodide, CF3C(O)I
Authors: Védova C. O. Della , Aymonino P. J. , Bravo R. D. 
Published: May 2005

AbstractIR, Raman and UV spectra of CF3C(O)I have been obtained and assigned to the expected vibrational normal modes of the molecule and electronic transitions in the CO group. Internal force constants were calculated from vibrational data. The results agree with data reported for other CF3C(O)X compounds.
Infrared and resonance Raman spectra of hydroxophthalocyaninatomanganese(III)
Authors: Quinzani O. V. , Jubert A. H. , Aymonino P. J. 
Published: May 2005

AbstractThe infrared and resonance Raman spectra of the solid complex hydroxophthalocyaninatomanganese(III) were obtained. The excitation profiles of some vibrational modes show resonance within the electronic bands in the visible region, and on this basis several vibrational and electronic absorption bands are assigned.
Raman spectral studies of ion–molecular interactions of lithium bromide and lithium iodide with dimethyl sulphoxide
Authors: Ramana K. Venkata , Singh Surjit 
Published: May 2005

AbstractRaman spectra in the CH and SO stretching and SO bending regions are reported for solutions of lithium halides and tetrabutylammonium bromide (TBAB) in dimethyl sulphoxide (DMSO) and DMSO‐d6. The CD stretching band of DMSO‐d6 shows two components in solutions of TBAB with DMSO‐d6, whereas the CH stretching band of DMSO for solutions of LiX (X = Br and I) in DMSO show some broadening and asymmetry in the low‐frequency region. The SO stretching bands show changes in band shapes and band contours in solutions of electrolytes in DMSO. Fourier deconvolution of CH and SO stretching bands were carried out to gain more information regarding number of components present under the broad structured bands. All the solutions show a significant decrease in the intensity of the SO bending bands when compared with the neighbouring CS bending band. The results are discussed in terms of anion‐ and cation–molecular interactions with DMSO.
Hypersonic behaviour of bismuth germanium oxide (Bi4Ge3O12)
Authors: Prieto C. , Pelous J. , Boissier M. , Contreras L. 
Published: May 2005

AbstractBrillouin scattering was performed between 80 and 300 K in order to study the hypersonic properties of Bi4 Ge3O12 crystals. The velocity and the attenuation of longitudinal acoustic phonons propagating along the [100] direction were measured for frequencies near 34 GHz. The Brillouin shift shows a variation with temperature which is five times lower than that observed in another bismuth germanium oxide, Bi12 GeO20. The hypersound attenuation is also very low and seems to be independent of temperature.
Raman spectroscopic investigation of N‐alkylurotropinium polyiodides
Authors: Mittag H. , Stegemann H. , Füllbier H. , Irmer G. 
Published: May 2005

AbstractN‐Alkylurotropinium polyiodides, UrRIx, with different iodine contents and different sizes of alkyl group were investigated by Raman spectroscopy. The spectra were recorded for wavenumber shifts up to 500 cm−1. It was found that the triiodides, UrRI3, contain a symmetrical linear I3− ion. The pentaiodides, UrRI5, contain no triiodide unit; the anion structure can be described as nearly symmetrical, rectangular L‐shaped I5−. An interpretation of the Raman spectra of the heptaiodides, UrRI7, is that the anion corresponds to an I5−. I2 structure. This is the first proof of such a heptaiodide. A review of previously published data on the Raman spectra of polyiodides is also given.
Vibrational spectra of trifluoromethylthiosulphenyl chloride, CF3SSCI
Authors: Della Védova C. O. 
Published: May 2005

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 suggest C1 symmetry. 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 compounds.
Hyper‐Raman scattering with circularly polarized light
Authors: Subramanian R. , Krishnamurthy N. , George S. 
Published: May 2005

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 with D3h symmetry is presented.
Rotational diffusion in methyl iodide: Bandshape analysis of degenerate vibrational modes
Authors: Wang S. P. , Yuan P. , Schwartz M. 
Published: May 2005

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 ν3 agreed well with earlier reported results. The degenerate CH3 stretching 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 of D∥ as that calculated from ν4. The room‐temperature infrared spectral intensities of ν5 were 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 ν4 and ν5. These results demonstrate the utility of analyzing degenerate vibrational modes to determine the parallel diffusion coefficients in C3v molecules.
Surface‐enhanced Raman spectra of acid radicals adsorbed on silver particles
Authors: Chun‐ping Zhang , Feng‐qi Yu , Guang‐yin Zhang 
Published: May 2005

AbstractThe surface‐enhanced Raman spectra of NO3− and B(OH)4− were obtained by adding metal ions to a silver sol containing these anions, and the enhancement factor was estimated to be 104‐105 for NO3−. We think this is because metal ions form a complex compound with NO3− on the surface of the silver particles, leading to the formation of an O–Ag bond via the lone pair of electrons of the NO3−. The Raman spectrum of this bond has been observed. In addition, a tentative method for testing for trace ions is proposed.
Spectroscopic properties of methyl thiolfluoroformate, FC(O)SCH3
Authors: Della Védova C. O. 
Published: May 2005

AbstractDetailed IR and Raman data for methyl thiolfluoroformate, FC(O)SCH3, point to the existence of a trans (F, CH3) conformer with Cs symmetry in both the vapour and liquid phases. For all but the torsional modes of this conformer, wavenumbers are reported and were used to calculate an approximate force field. The study was complemented with the characterization of the compound using the 13C 19F and 1H NMR, UV and mass spectra. A semi‐empirical calculation was performed for the molecule, and the deduced force constants were compared with those derived from experimental data.
Raman spectral study of the Mg(ClO4)2NaNCSH2O system at ambient and elevated temperatures
Authors: Antić‐Jovanović A. , Jeremić M. , Lalić M. , Long D. A. 
Published: May 2005

AbstractRaman spectra of Mg(ClO4)2NaNCSH2O mixtures were analysed as a function of the concentration ratio of the components at ambient and elevated temperatures. The strong perturbation of the thiocyanate spectrum observed in the regions of the ν1 and ν3 vibrations is interpreted in terms of complex formation. Band intensity measurements of resolved bands gave evidence for two complex species: [MgNCS]+ and [Mg(NCS)2], the former being discernible over the whole concentration range studied. The variations in the spectrum of the Td perchlorate ion at very low water‐to‐salt molar ratios are explained as indicating a coordination of ClO4− unit and lowering of the symmetry of C2ν.
Vibrational spectra and normal coordinate analysis of monohalogenated nitrobenzenes
Authors: Muralidhar Rao P. , Ramana Rao G. 
Published: May 2005

AbstractThe Raman and infrared spectra of o‐, m‐ and p‐fluoronitrobenzenes, o‐, m‐ and p‐chloronitrobenzenes, m‐ and p‐bromonitrobenzenes and o‐, m‐ and p‐iodonitrobenzenes were measured. Far‐infrared and Raman polarization measurements were made wherever possible. A normal coordinate analysis was carried out for both the in‐plane and out‐of‐plane vibrations of these molecules using an 82‐parameter modified valence force field. An overlay least‐squares technique was employed to refine the force constants using 378 frequencies of the molecules to obtain a converged set of meaningful force constants. The reliability of the force constants so obtained was tested by making a zero‐order calculation for o‐bromonitrobenzene. The potential energy distributions and eigenvectors calculated in the process were used to make unambiguous vibrational assignments of all the fundamentals.