bluuebunny/crossref_metadata_2025 huggingface dataset:
Raman spectra of matrix‐isolated and solid chromiumhexacarbonyl
Authors: Scheuermann Walter , Nakamoto Kazuo
Published: May 2005

The Raman spectra of Cr(CO)6 have been measured in an Argon matrix at 13 K and in the solid state at 292 and 13 K. As expected only the A1g, Eg and F2g modes were observed in the matrix spectra. The ν4(Eg) mode was observed split into a polarized and a depolarized component. This indicated a lowering of the symmetry from Oh to D4h or one of its subgroups. Depolarization ratios obtained in the matrix were close to values obtainable in liquids. In the low temperature solid state spectra all thirteen fundamental modes as well as several overtones and combination bands were observed. The six modes ν5(F1g) (inactive), ν6(F1u), ν7(F1u), ν8(F1u), ν12(F2u) (inactive) and ν13(F2u) (inactive), which were previously inferred from overtones and combinations, were observed for the first time.
Mechanistic interpretations of vibrational dephasing processes in 1,1,1‐trichloroethane by spontaneous Raman spectroscopy
Authors: Baglin F. G.
Published: May 2005

The Raman signals from modes ν1, ν2, ν3, 2ν2, and 2ν8, of 1,1,1‐trichloroethane have been examined by varying the concentration of this molecule in several solvents. In addition temperature studies were conducted, including data from the disordered solid phase of the neat sample. The results of these studies show that (a) the fundamentals (ν1, ν2, and ν3) are involved in a dephasing process controlled by the intramolecular potential function, (b) dephasing processes of the overtones are dominated by intermolecular processes and (c) the ν2 and ν3 modes of this molecule show very little dilution effects (some broadening), whereas the same modes of the structurally similar molecule CH3I show a definite narrowing in similar solvents. The theoretical model, proposed by Rothschild, is used to strengthen the interpretative case offered for the mechanistics of the dephasing processes of the fundamental modes.
A polarized infrared and Raman spectroscopic study of the electrooptic crystal m‐nitroaniline. I—assignments of internal vibrations
Authors: Szostak M. M.
Published: May 2005

The spectra of m ‐ nitroaniline solution in the middle infrared region (300–4000 cm−1) and in the Raman scattering region (150–1650 cm−1) as well as the polarized infrared (240–3500 cm−1) and Raman (170–1650 cm−1) spectra of monocrystalline samples of this compound have been measured. The dichroic ratios of infrared bands for (010) platelets and the depolarization ratios of the bands in the Raman spectra of acetone solution were determined and compared with theoretical values. On the basis of the results obtained and the assignments previously given by other authors, the assignments of all fundamentals of m ‐ nitoaniline have been either confirmed or proposed for the first time. Some relations between the electronic transition directions and the relative intensities of the infrared bands have also been found.
High temperature Raman scattering in Sm0.8La0.2AlO3 Compound: A relation to the phase transition in rare earth orthoaluminates
Authors: Alain P. , Coutures J. P. , Piriou B.
Published: May 2005

Raman spectra of molten Sm0.8La0.2AlO3 have been recorded from room temperature to 1470 K. Experimental results show that a first‐order phase transition occurs at 580 K and that two phonon modes appear very unstable in the high temperature phase. Comparison with Raman data obtained on rare earth aluminate single crystals indicates that these ‘soft’ modes may be associated with a rhombohedral to cubic phase transition.
On the possibility of recording picosecond spontaneous Raman spectra
Authors: Valat P. , Tourbez H.
Published: May 2005

We report the conditions under which it is possible to record the complete spontaneous Raman spectrum of a sample excited by a single ultra‐short laser pulse. A method for exciting such spectra is described; it uses cylindrical lens focusing of the laser and enables us to get the same amount of Raman signal from much lower energy densities.
Etude par Spectrométrie Raman Rapide de la Cinétique d'Addition de l'Acide Chlorhydrique à des Doubles Liaisons Conjuguées: Cas du cis‐2, trans‐4‐Hexadiène
Authors: Beny J. M. , Bassez C. , Sombret B. , Wallart F.
Published: May 2005

The kinetic study of thermal dehydrochlorination of 4‐chloro‐2‐hexene (model of an allylic unstable structure occurring in polyvinyl chloride during its degradation) has shown that the reaction is reversible and has an ionic mechanism. The activation energies for the addition of hydrogen chloride to conjugated double bonds of cis‐2‐, trans‐4‐hexadiene in ethanol or dichloroethane have been determined by rapid Raman spectroscopy as 71.1 ± 10.4 kJ mol−1 and 36.8 ± 5.0 kJ mol−1 respectively from plots of the intensity ratio Iν(CC)/I against time at various temperatures.
Infrared and Raman studies of rotational isomerism in meso‐2,3‐dibromo‐1,4‐dichlorobutane
Authors: Crowder G. A.
Published: May 2005

Infrared and Raman spectra were obtained for meso‐2,3‐dibromo‐1,4‐dichlorobutane in the solid state and in solution. Only one conformation is present in the solid, it being one with a center of symmetry (all carbons and chlorines coplanar, bromines on opposite sides of that plane). The other two stable conformers are present to a small extent in solution. A vibrational assignment of the solid state bands is proposed.
Evidence for short range orientation effects in pure liquid SO2 from vibrational Raman spectroscopy
Authors: Kamoun Mohamed
Published: May 2005

In the Raman spectrum of pure liquid SO2 a difference is observed between the wavenumbers of the isotropic and anisotropic components of the totally symmetric vibrations ν1 and ν2, the anisotropic component being at a higher frequency than the isotropic one. The separations are Δν1 = 5 cm−1, Δν2 ≃ 3.5 cm−1. This effect is approximately independent of temperature in the range −60 to +40°C. It disappears with dilution of SO2 in an inert solvent. The same shift is observed in solid SO2. Mirone and Fini2 and Josien3 have observed and interpreted such an effect in the case of larger molecules. They assume the liquid to be composed of clusters in which the molecules are partially ordered. In the case of SO2 our calculations based on such a model are in good agreement with the experimental results for ν2 but not for ν1.
Vibrations de Basses Fréquences du Cristal de m‐Chloronitrobenzène
Authors: Le Calvé N. , Romain F. , Pasquier B.
Published: May 2005

Polarized Raman and infrared spectra of meta‐chloronitrobenzene single crystals have been investigated in the ranges 140‐5 cm−1 and 140–20 cm−1 respectively. They are compared to those of meta‐bromonitrobenzene recorded for comparison. All 21 lattice vibrations expected have been observed and assigned to their symmetry species and in terms of translational and rotatory vibrations. The only intramolecular mode, a NO2 torsion, has been identified near 93 cm−1 giving rise to four components in the crystal. The corresponding potential barrier V2 = V*/4 has been calculated.
Resonance Raman spectrum of crystal violet
Authors: Angeloni L. , Smulevich G. , Marzocchi M. P.
Published: May 2005

The preresonance Raman spectra, taken under various conditions, of crystal violet have been obtained using the exciting lines of an Ar+ laser. The analysis of the Raman data and of the IR and UV visible absorption spectra allowed us to determine the structure of the ion (propeller‐like in shape with D3 symmetry), to characterize the unstable single protonated dye cation, and to propose a detailed vibrational assignment in terms of coupled vibrations of the substituted benzenes. In addition, the measurements of the Raman excitation profiles furnished information on the vibronic couplings and provided evidence for a close correlation in the resonance mechanisms between crystal violet and benzene and its monosubstituted derivatives.
Anomalous polarization in the resonance Raman spectra of acetylene–cumulene dehydro annulenes
Authors: Fujimoto Etsuko , Yoshimizu Nobuaki , Maeda Shiro , Iyoda Masahiko , Nakagawa Masazumi
Published: May 2005

Anomalous polarization (ρ = 3/4 ˜∞) has been observed in the resonance Raman spectra of some acetylenecumulene dehydro annulenes of a D2h rectangular configuration. Because of no orbital degeneracy, the observed anomaly may certainly be explained by the vibronic coupling of the resonant level with nearby states. From the nature of those relevant electronic levels, the anomalous lines are assigned to the B1g modes of vibration. For a typical anomalous polarization case, the polarization dispersion and excitation profile have been investigated.
Low frequency vibrational spectra of bromo‐and iodoantimonates
Authors: Jagodzinski Paul W. , Laane Jaan
Published: May 2005

The Raman and far‐infrared spectra of a dozen antimony halide complexes of formula SbX6−3, SbX5−2, Sb2X9−3 and SbX4−1 have been recorded and analyzed for X = Br and I. The stretching frequencies for the bromo complexes range from about 135 to 220 cm−1 for external bonds and from about 110 to 130 cm−1 for bridging bonds. For the iodo complexes the ranges observed are 138–174 cm−1 (external) and 87–127 cm−1 (bridging). Approximate force constants were calculated for the anions and these were compared to values previously determined for halobismuthates. In general, the ordering of the force constants was found to be SbBr>SbI˜BiBr>BiI. As was found for the bismuth complexes, the stretching force constants were greatest for bonds in the anions in which the largest number of other bonds were to bridging halogens.
Polarized Raman and resonance Raman spectra of single crystals of mixed valence metal complexes
Authors: Papavassiliou G. C. , Layek D. , Theophanides T.
Published: May 2005

Polarized Raman and resonance Raman spectra of single crystals of one‐dimensional mixed valence platinum complexes have been recorded and studied. Polarized Raman spectra of single crystals of [M(II) (en)2M(IV)(en)2X2](ClO4)4, where X = Cl or Br, M = Pt or Pd and en = ethylenediamine, show strong resonance enhancement of the…XM(IV)X…symmetric stretching vibration in the chain. Analysis of the spectra shows that the metals are coupled in the chain through the halide atoms. The coupling occurs by electron charge transfer via the dz2‐orbitals of the metal from the lower to the higher oxidation state.
Vibrational spectra of C2v deuterium substituted pyridines. 2—Pyridine, pyridine‐4‐d, pyridine‐2,6‐d2 and pyridine‐2,4,6‐d3
Authors: Dilella Daniel P. , Stidham Howard D.
Published: May 2005

Pyridine‐4‐d, pyridine‐2,6‐d2 and pyridine 2,4,6‐d3 have been prepared. The isotopic composition and label specificity of each of several preparations were verified by mass spectroscopy and proton NMR. The liquid phase Raman and the liquid and vapor phase infrared spectra are reported for these materials and for pyridine at room temperature. A new vibrational assignment consistent with frequency sum and product rule constraints is proposed. Thermodynamic functions calculated from the pyridine assignment are found to be in good agreement with published experimental values.
Vibrational spectra and conformations of alkyl substituted three‐membered ring compounds: Ethylcyclopropane, isopropylcyclopropane and ethyloxirane
Authors: Nease A. B. , Wurrey C. J.
Published: May 2005

The infrared spectra (from 4000 to 200 cm−1) and Raman spectra of ethylcyclopropane, isopropylcyclopropane and ethyloxirane have been recorded in solid, liquid and vapor phases. From the spectral data, ethylcyclopropane has been shown to exist solely in the gauche conformation in all three states of matter. Likewise, isopropylcyclopropane exists solely in a bisected conformation having a mirror plane of symmetry. On the other hand, however, in the gas phase ethyloxirane exists as an equilibrium mixture of the two nonequivalent gauche rotameric forms. In all cases, steric repulsions between methyl hydrogens and β‐ring hydrogens preclude the existence of possible conformers where a methyl group is situtated over (cis) the three‐membered ring. Tentative vibrational assignments have been proposed for major spectral bands of all three molecules.
Raman band intensities of some local group modes of α‐Glycine, L‐alanine and DL‐alanine crystals
Authors: Machida Katsunosuke , Mori Michiyo , Kagayama Akira
Published: May 2005

Band intensities in the polarized Raman spectra have been measured for the CO2− stretching, the CH2 stretching and the CH2 bending modes of α‐glycine crystal and the CO2− stretching and the CH3 symmetric deformation modes of L‐ and DL‐alanine crystals. Variations in the relative band intensities on the change of the scattering geometry have been elucidated by applying the oriented gas model to the local groups, –CH2, –CH3 and –CO2−, of these amino acid crystals. The calculated values of the components of the derived polarizability tensors are consistent with the geometry of the groups. The depolarization ratios estimated from the calculated anisotropy of the polarizability tensors have been compared with those observed for aqueous solutions.
A study of some vibrational band intensities in the pre‐resonance Raman spectra of naphthalene, phenazine, pyrazine, cinnoline and quinazoline
Authors: Aminzadeh A. , Fawcett V. , Long D. A.
Published: May 2005

Experimental studies of the variation of intensity with excitation wavenumber of various vibrational bands in the Stokes Raman spectra of the following molecules are reported: naphthalene, pyrazine, phenazine, cinnoline and quinazoline. The results are discussed in terms of the Albrecht–Hutley theory of pre‐resonance Raman intensities and the electronic states involved in the pre‐resonance enhancement identified.
Etude par Spectroscopie et Microscopie Raman de Phases Oxyde de Molybdène Déposé sur Alumines
Authors: Sombret B. , Dhamelincourt P. , Wallart F. , Muller A. C. , Bouquet M. , Grosmangin J.
Published: May 2005

Raman spectroscopy and microscopy have been used to study some catalysts: Mo supported on alumina. Different Mo species were found, depending upon the amount of molybdenum deposited on the carrier. At low coverages (4% wt MoO3) distorted molybdate tetrahedra were observed. Increasing the surface coverage resulted in the formation of a polymolybdate phase with octahedrally surrounded molybdenum. Additionally, ‘bulk MoO3’ appeared when amounts were above 16% wt MoO3. When the supports were washed during their preparation with aqueous NH4OH and HNO3 solutions, preferential formation of polymolybdate phase was observed. In case of washing with alkaline solution ‘free MoO3’ was also detected. Finally using the Raman microprobe MOLE, a map giving the distribution of the different species at the surface of support was obtained.
On the tautomerism of the thymine anion in the solid state: A Raman and infrared study
Authors: Lippert Bernhard
Published: May 2005

Solid state infrared and Raman spectra of thymine, thymine monohydrate, three types of chloro(thyminato‐N1)ethylenediamineplatinum(II) complexes and three types of potassium thyminate (trihydrate, monohydrate, anhydrous compound) are reported and compared. The effects of hydrogen bonding, intermolecular coupling, crystal symmetry and tautomerism are discussed. For the anhydrous potassium thyminate a tautomeric structure, different from that found in the tri‐ and monohydrate, is postulated.
Vibrational spectra and structure of cyclopropyl isothiocyanate
Authors: Wurrey C. J. , Krishnamoorthi R. , Nease A. B.
Published: May 2005

For cyclopropyl isothiocyanate, the infrared (4000–200 cm−1) spectra in all three phases and the Raman spectra of the liquid and solid phases have been recorded. From Raman depolarization data and infrared gas phase band contours it has been concluded that cyclopropyl isothiocyanate exists in the cis conformation. No evidence for the existence of other conformations was found in the spectra. An assignment for 24 of the 27 fundamental vibrational modes has been proposed and this assignment has been shown to be in excellent agreement with vibrational assignments for other monosubstituted cyclopropanes and a number of isothiocyanate compounds.
Benzisoxazoles ‐1,2 et ‐2,1: Analyse vibrationnelle infrarouge et Raman
Authors: Mille G. , Guiliano M. , Angelelli J. M. , Chouteau J.
Published: May 2005

Raman (3200–100 cm−1; liquid state) and infrared spectra (4000–200 cm−1; vapour, liquid state, and dissolved in inert and proton acceptor solvents) of −1,2 and −2,1 benzisoxazoles have been recorded. Their experimental analysis have allowed a complete attribution of the fundamental vibrations and of some overtone and combination vibrations of these heterocycles.
Etude de la Dispersion Angulaire des Modes Polaires d'un Monocristal de Phosphite de Lithium LiH2PO3
Authors: Beys Louis , Hillaire Paul
Published: May 2005

The angular dispersion of polar phonons with wave vectors k(k » (ω/c)) rotating in the planes of symmetry of the orthorhombic LiH2PO3 single crystal has been observed with Raman scattering experiments at T = 293 K in the regions 250–600 cm−1 and 850–1350 cm−1. The agreement of the experimental data with the existing theories of angular dispersion is very satisfying.
Interference effects in the high Resolution CARS spectra of gases
Authors: Laane J. , Kiefer W.
Published: May 2005

The CARS spectra of gas‐phase molecules have contributions from both real and imaginary components of the third‐order non‐linear susceptibility. When the spectral lines are closely spaced as in the high‐resolution CARS spectra (e.g. ˜ 0.03 cm−1) of the Q‐branches of diatomic molecules, considerable interference between the lines occurs for the contribution of the real part of the susceptibility, which causes asymmetry in the band profiles. The magnitude of the interference is dependent on the bandwidths Γ which are themselves primarily due to pressure broadening at high and medium pressures and due to Doppler broadening at low pressure. In this work the CARS spectra of two individual lines and of the diatomic molecules O2, N2 and NO have been calculated for a number of different linewidths. The effects of interference wereshown to result in substantial spectral differences for the various values of Γ.
Solid state vibrational spectroscopy. 9—A kinetic study, using Raman spectroscopy, of the solid state thermal decompositions of alkali metal peroxydisulphates
Authors: Cleaver Kevin D. , Davies J. Eric D.
Published: May 2005

The kinetic behaviour of the solid state thermal decomposition of peroxydisulphate to pyrosulphate, M2[S2O8] → M2[S2O7], M = Na, K, Rb, Cs, has been studied by following the temporal decrease in the intensity of the Raman band arising from the vs(SO3) mode of [S2O8]2−. The data are best analysed using a conventional kinetic approach rather than the Avrami–Erofeev treatment normally applied to solid state reactions. Although the salts display different kinetic orders, 1.5, 2.0, 1.0 and 1.0 for the Na, K, Rb and Cs salts respectively, the lack of crystallographic data does not allow us to rationalize these differences.
Activité Raman du m‐Chloronitrobenzène, Cristal Piézo‐électrique
Authors: Pigenet Claude , Le Calvé Nicole , Pasquier Bernadette
Published: May 2005

The piezo‐electric crystal m‐C6H4ClNO2 was studied by Raman scattering. TO–LO splitting of 1–7 cm−1 was observed for some internal modes and correlated to the infrared intensities. The observed Raman lines corresponding to the vsNO2 mode are interpreted through an analysis using G0(k,–k) subgroups of the factor group G0(0). The effective dynamical charges were calculated. The polaritons corresponding to the vs(NO2)A1 mode and skeletal mode at 1123 cm−1 were observed.
A fast method for calibrating cosecant drive monochromators
Authors: Bergström G. , Forss S. , Stenman F.
Published: May 2005

A fast method for adjusting and calibrating cosecant drive monochromators is described. It is based directly on the analytical expression for the calibration curve as derived directly from the mechanical construction of the grating drive mechanism.
Time‐resolved Raman spectra of photoexcited semiconductor plasma
Authors: Luzzi Roberto , Vasconcellos Áurea R.
Published: May 2005

A theoretical study of time‐resolved Raman scattering by a highly photoexcited semiconductor plasma is developed. The scattering cross‐section is calculated using the Zubarev non‐equilibrium ensemble method to describe the macroscopic evolution of the far from equilibrium plasma. Numerical results appropriate for GaAs are presented as an illustration.
Resonance‐Raman and electronic absorption spectra of O ions in γ‐irradiated Cd(ClO3)2
Authors: Campelo L. C. , Melo F. E. A. , Mendes Filho J. , Katiyar R. S. , Vargas H.
Published: May 2005

Resonant vibrational Raman measurements of the O ion modes in γ‐irradiated Cd(ClO3)2 single crystals are reported. It is concluded that the O ions occupy only one non‐equivalent site in the host lattice, in accordance with the ESR measurements previously reported. Resonance enhancement of the fundamental mode and its overtones as a function of the exciting wavelength is also investigated. The activation energy is determined by a simple direct calculation.
Theory of the electronic Raman effect in intermediate valence compounds
Authors: Foglio Mario E.
Published: May 2005

We present an approximate expression for the electronic Raman scattering intensity of localized impurities, and we employ this result in a simple model of intermediate valence compound with a hybridization term of the Anderson type. We have calculated the relevant time correlation functions using a Green's function technique. Using the published estimates of p, the probability of finding a Sm ion as Sm3+, determined from the lattice parameters, we were able to compare our expression for the Raman linewidth with published measurements of the linewidth in Sm1–xYxS. The theoretical dependence of the linewidth with x at 300 K gives only qualitative agreement with experiment. Out theory reproduces fairly well the independence of the line shape when samples with 0.15 < x < 0.3 underwent the temperature‐induced black to gold transition.
Resonance in the Raman scattering of CaF2, SrF2, BaF2 and diamond
Authors: Grimsditch M. , Cardona M. , Calleja J. M. , Meseguer F.
Published: May 2005

The dependence of the first order Raman scattering efficiency of CaF2, SrF2, BaF2 and diamond on photon energy ωL has been measured with different techniques. We find that in the visible these cross‐sections increase with ωL much faster than ω. This result has important implications as CaF2, for instance, is usually used as a standard scatterer in resonant Raman experiments, with the assumption that its efficiency is excatly proportional to ω. The possible sources of these anomalies are discussed.
Theory of light scattering by surface polaritons in gyrotropic media
Authors: Maradudin A. A. , Wallis R. F.
Published: May 2005

In recent years considerable effort has been devoted to the experimental and theoretical investigation of surface polaritons in dielectric and conducting media. In metals and semiconductors containing free carriers, interesting phenomena are exhibited by surface plasmon polaritons in the presence of an external magnetic field. A useful tool for probing such phenomena is the inelastic scattering of light. The theory of light scattering from surface polaritons can be conveniently developed in terms of the electromagnetic Green's tensor for the medium with a free surface. We have calculated the elements of the electromagnetic Green's tensor for a homopolar medium containing free carriers which is placed in a constant magnetic field normal to the surface. An expression for the light scattering cross‐section has been derived. Other applications of the electromagnetic Green's tensor are discussed.
A note on a quantum theory of surface enhanced Raman scattering
Authors: Lee Ting‐Kuo , Birman Joseph L.
Published: May 2005

A ‘coupled mode’ set of eigenfunctions is obtained for investigations of the quantum theory of surface enhanced Raman scattering by a physiadsorbed molecule on a metal surface. The enhancement ratio R(ω) for scattering cross‐section of adsorbed to free molecules is calculated. The theory is applied to the pyridine on silver system. In the classical limit, using a geometry with flat silver surface, the ‘image enhancement’ model is recovered, and a large enhancement can be forced if unrealistic values of parameters are used. In the correct quantum theory a sharply peaked enhancement of about 10−3 of that reported can be obtained at laser energy about 3.7 eV. The conventional image model is thus not supported by the quantum theory. Surface roughness needs to be incorporated into this coupled mode theory.
Spectroscopy using laser‐pumped laser oscillators
Authors: Deshazer L. G.
Published: May 2005

Transition cross‐sections were measured independent of active atom concentration and extrinsic loss using a laser‐pumped CW laser oscillator. Extrapolation of the linear input–output characteristic of a CW oscillator to null pumping rate determined the saturation power from which is determined the laser cross‐section. Laser cross‐sections were measured for Nd3+ in YAG and YVO4.
High pressure and variable temperature study of the Raman spectrum of camphor
Authors: Wilkinson G. R. , Medina J. A. , Sherman W. F.
Published: May 2005

Raman spectra of d‐camphor in the lattice mode region are presented for sample pressures in the range up to 25 kbar and temperatures between 77 K and 350 K. Out of the five different structures that have been studied, the Raman spectra have previously only been available for the two that are stable under zero pressure conditions.
On the reststrahlen spectrum of yttrium iron garnet
Authors: Häussler K. M. , Falge H. J. , Brandmüller J.
Published: May 2005

The reststrahlen spectrum of yttrium iron garnet is investigated by infrared reflection measurements using an ATR‐hemicylinder or an externally applied magnetic field, respectively. Data on infrared inactive phonons and the magnetic influence on the reststrahlen bands are reported.
The principle of ‘interacting spectra’ as a tool for analysis of the light scattering spectral distribution near phase transition points
Authors: Ginzburg V. L. , Sobyanin A. A. , Levanyuk A. P.
Published: May 2005

A principle is formulated which can be useful for the interpretation of experimental data on the scattered light spectrum near the phase transition points.
Lattice modes in the ferroelectric perovskites (Pb1–x Srx) TiO3
Authors: Burns Gerald , Dacol F. H.
Published: May 2005

In this paper we discuss the Raman data of the vibrational frequencies of the perovskite mixed system (Pb1–xSrx) TiO3, both at room temperature and at −160°C.
Light scattering from laser annealed ion implanted semiconductors
Authors: Balkanski M. , Morhange J. F. , Kanellis G.
Published: May 2005

Light scattering is shown to be a powerful tool for the investigation of laser annealed ion implanted semiconductors. The results reported here concern boron implanted in silicon which shows up as localized mode where in substitutional position and boron‐phosphorous pairs giving also localized modes. The characteristics of the amorphous layer obtained after ion inplantation are also investigated by Raman spectroscopy and detailed results on the amorphous crystalline transition achieved by laser annealing are presented.
The anomalous temperature variation of the symmetric stretching vibration νs(H2O) in hexa‐aqua metal (II) hexafluorosilicate (IV)
Authors: Jenkins T. E. , Lewis J.
Published: May 2005

The anomalous temperature dependence of the linewidth of the νs(H2O) symmetric stretch vibration in hexa‐aquo metal (II) hexafluorosilicate (IV) salts is discussed in terms of anharmonic interactions. It is shown that the main contribution to the linewidth is an elastic scattering process between νs(H2O) and the torsional vibration of the water molecules leading to a pure vibrational dephasing. Contributions to the linewidth due to inelastic decay into other vibrational states are also discussed.
Vibrational spectroscopic studies of a new class of oligophosphate glasses of biological interest
Authors: Bertoluzza A. , Fagnano C. , Fawcett V. , Long D. A. , Taylor L. H.
Published: May 2005

Vitreous biomaterials with chemical composition similar to that of bone may be formed by treating mixtures of vitreous sodium polyphosphate, Graham's salt and hydroxylapatite. The Raman and infrared spectra of a range of such materials are reported and discussed in relation to their structure.
Spectres Raman du Monocristal de Fumarate de Potassium Dihydraté, K2H2C4O4,·2H2O
Authors: Maury Luc , Bardet Lucette , Brunel René , Vierne Raymond
Published: May 2005

Raman spectra of a single crystal K2H2C4O4.2H2O and of polyrystalline K2H2C4O4.2H2O, K2H2C4O4.2D2O, and K2H2C4O4 have been recorded at room temperature from 10 to 3500 cm−1; Raman and infrared data are compared. The existence of hydrogen bondCH…︁O is confirmed.
Resonance Raman studies of transition metal peroxo complexes: 2‐The purple intermediate formed in the reactions of iron(II) and iron (III)ethylenediaminetetraacetate with superoxide and hydrogen peroxide, respectively
Authors: Hester R. E. , Nour E. M.
Published: May 2005

Resonance Raman spectra are reported for the purple intermediate formed in the reactions of [Fe(II)(EDTA)]2− and [Fe(III)(EDTA)]− with O2− and H2O2, respectively, using several different excitation wavelengths. The spectra show only two resonance‐enhanced bands, at 472 and 824 cm−1. The band intensity excitation profiles for these two are different, demonstrating that the resonance effects observed are associated with two different electronic transitions. The 472 cm−1 band is assigned to the ν(FeN) mode and the 824 cm−1 band to ν(OO). The structure of the species is shown to be the peroxide ion complex [Fe(III)(EDTA)(O2)]−. The O22− → Fe3+ electronic charge‐transfer transition is assigned at 454 nm.
Resonance Raman studies of transition metal peroxo complexes: 6—The peroxodicobalt(III)—oxime complexes
Authors: Hester R. E. , Nour E. M.
Published: May 2005

Resonance Raman spectra have been determined at −60°C for a series of complexes of the general form [(L)(D2H2)CoO2Co(D2H2)(L)], where D is the dianion of dimethylglyoxime and L is pyridine, (C2H5)3N, (CH3)2S, (C6H5)3P, (C6H5)3As and (C6H5)3Sb, these ligands being coordinated trans‐axially to the dioxygen. The spectra show bands in the region 810–835 cm−1 which are assigned to the ν(OO) mode and the ν(CoO) mode is assigned in the region 550–575 cm−1. The effect on the observed ν(OO) wavenumber of changing the ligand L shows how σ‐ and π‐donor effects of the ligands are transmitted through the metal. The ν(OO) band intensity excitation profile demonstrates that the O2− → Co3+ CT transition is to be assigned at 550 nm. Comparison between the nature of the cobalt‐oxygen binding in the oxime and those of the cyanide and salen systems are discussed.
Band contours of the degenerate fundamental bands of cyclohexane and cyclohexane‐d12 determination of the coriolis constants
Authors: Bien T. , Doege G. , Arndt R.
Published: May 2005

The Raman spectra of the degenerate bands of cyclohexane and cyclohexane‐d12 have been recorded at medium resolution in the gas phase. The computer simulation of the band contours has allowed to determine the Coriolis coupling constants ζ19, ζ20, ζ21, ζ22, ζ23, and ζ24.
Spectre Raman de Translation de la Glace Hexagonale Monocristalline: Effets Directionnels
Authors: Faure P. , Chosson A.
Published: May 2005

It is shown using Raman scattering experiments with appropriate geometries that the directional effects which have been observed in the spectrum of ice Ih are not of the same kind as occur in ordered piezoelectric crystals, but are caused by a modification in the activity of the one phonon density of states or of certain branches of the dispersion curves, produced by the conditions of incidence and observation.
Spectres Raman de Résonance de Dérivés Substitués de l'Aminoazobenzéne en Solution Acide
Authors: Merlin J. C. , Lorriaux J. L. , Dupaix A. , Thomas E. W.
Published: May 2005

The resonance Raman spectra of aminoazobenzene derivatives in acidic solution are investigated. The marked spectral changes observed on decreasing pH are related to transformations between azo and quinoid forms. The pKa value of 4‐amidino, 4′‐diméthylaminoazobenzene obtained from intensity measurements is in good agreement with the value obtained from visible absorption measurements. Comparison of resonance Raman spectra of some substituted aminoazobenzene derivatives and the quinoid form of an hydroxyazobenzene derivative enable a more complete assignment of the bands observed between 900 and 1700 cm−1 to be made. All the spectra are rather similar and the various ring substituents are not resonance Raman active. The influence of the NHN  vibration on resonance Raman spectra of the quinoid forms is demonstrated using deuterium substitution. In strong acid solution a second protonation occurs; a tautomeric equilibrium between azo and quinoid forms of aminoazobenzene derivatives is demonstrated using different exciting laser lines.
The vibrational spectrum of the benzophenone molecule
Authors: Blažević J. , Colombo L.
Published: May 2005

The vibrational spectrum of the benzophenone molecule has been studied using Raman spectroscopic techniques. The assignment of the observed bands has been supported by a normal mode calculation. Special attention has been paid to the interpretation of the low‐frequency modes.
Vibrational study of the dynamic disorder in nickelocene and ferrocene crystals
Authors: Chhor K. , Lucazeau G. , Sourisseau C.
Published: May 2005

Raman and infrared spectra (10–400 cm−1) of Ni(C5H5)2, Fe(C5H5)2 and of their perdeuterated derivatives (d10) have been recorded in the 30–300 K temperature range. A new assignment for some internal modes is proposed. The temperature dependence of the low frequency spectra (10–200 cm−1) and quasi‐elastic neutron scattering results are discussed in terms of dynamical disorder coming from molecular conformational fluctuations. The elastic incoherent structure factor (EISF) measured from neutron scattering on Ni(C5H5)2 is compatible with 2π/5 ring jumps involving an activation energy of 1.5 kcal mol−1, while Raman band broadenings are interpreted in terms of large amplitude torsional motions associated with an activation energy of about 0.5 kcal mol−1. A qualitative representation of the potential driving the torsional motion is proposed and it is pointed out that the intermolecular potential plays an important role. Finally, although the conformational fluctuations can be responsible for the pretransitional effects, they take part only for 15% of the enthalpy variations in the phase transition of Fe(C5H5)2.
Raman and infrared study on the interactions between phospholipids and proton donors
Authors: Bertoluzza A. , Bonora S. , Fini G. , Morelli M. A.
Published: May 2005

Raman and infrared spectra of phosphatidylcholine‐acid mixtures (1:1) are reported and discussed in terms of both general structural and specific interactions as a function of the acidic strength of the proton donor. The infrared spectra indicate the formation of a strong, highly polarizable hydrogen bond with monochloro‐, dichloro‐ and trichloroacetic acids. The complete transfer of the proton from the donor to the phospholipid is observed with hydrochloric acid. The Raman data suggest conformational changes in the lateral packing of the acylic chains of the phospholipid. The importance of both these specific interactions, namely hydrogen bonding and structural modifications, in biological systems is discussed and related to biological activity.
The Raman spectrum of CF4
Authors: Lolck Jens‐Erik
Published: May 2005

The Raman spectrum of CF4 has been recorded from 300 to 1450 cm−1 at a spectral resolution of about 0.25 cm−1. All four fundamental bands and some overtone and hot bands have been observed. In the anisotropic fundamental bands (ν2, ν3, ν6) the basic J‐structure is partly resolved. Special attention has been paid to the ν2 and ν4 bands, as these two bands are essentially unperturbed. The analyses of ν3 and ν4 give two independent determinations of the ground state rotational constant B0 and the centrifugal distortion constant D 0 The best estimates thereof are B0 = 0.191134±0.000017 cm−1 and D0 = (4.7 ± 0.6) × 10−8 cm−1. In addition some upper state constants are determined; among these are the three band origins ν1 = 909.088 cm−1, ν2 = 435.399 cm−1, and ν4 = 631.057 cm−1, all believed to be accurate to about 0.01 cm−1. The overtone and hot bands yield information on the position of some overtone and combination states.
Continuum resonance Raman effect in halogen gases
Authors: Baierl P. , Kiefer W.
Published: May 2005

In a previous publication7 we have outlined a theory for continuum resonance Raman scattering in diatomics using irreducible spherical tensors. In the present paper we apply this theory to the halogen molecules 79Br2 and 127I2 and compare numerical calculations of the band profile of fundamental and overtones to experimentally obtained continuum resonance Raman spectra of these molecules.
Hydrogen bonding in dimethylsulphoxide‐proton donor interactions: A Raman and infrared study of the DMSO‐HCI system
Authors: Bertoluzza A. , Bonora S. , Fini G. , Battaglia M. A. , Monti P.
Published: May 2005

Dimethylsulphoxide (DMSO)‐hydrogen chloride interactions have been studied by means of Raman and infrared spectroscopy both in solid 1:1 adducts and in liquid mixtures with DMSO:HCl molar ratios >2. The deuterated analogue solid 1:1 (DMSO‐d6)‐DCl was also prepared and studied. Vibrational data suggest the presence of a (DMSOHOSMD)+ cation with strong (OHO)+ hydrogen bonds both in the solid adducts and in the liquid mixtures. In the solid adducts the (CIHCl)− anion may be present. A relation between some biological properties of DMSO and its protonation is suggested.
Raman and infrared spectra of pentachloroaniline
Authors: Faniran J. A. , Iweibo I. , Oderinde R. A.
Published: May 2005

Raman spectra of crystalline pentachloroaniline (PCA) have been measured. The infrared spectra have also been recorded for solid and solutions in CCl4 between 4000–200 cm−1. An assignment of the observed frequencies has been proposed for a Cs molecular symmetry based on related halogen substituted benzene derivatives. The molecule does not appear to self‐associate in CCl4 solutions although there is some evidence for a weak hydrogen bonding in the solid state.
Raman and infrared spectra of crystalline 9‐methyladenine and its methylmercury complexes
Authors: Savoie Rodrigue , Poirier Donald , Prizant Leonardo , Beauchamp André L.
Published: May 2005

The Raman and infrared spectra of polycrystalline samples of 9‐methyladenine and three of its methylmercury complexes have been recorded. These complexes include the N1‐coordinated and the N1‐coordinated‐NH2‐substituted derivatives, the third compound being probably N1‐and N7‐coordinated. Spectral changes occurring upon complexation are analysed, and comparisons are made with the corresponding changes in the spectra of various adenine derivatives which are known to form complexes with CH3Hg+ in aqueous solution.
Etude des Variations d'Intensité des Polaritons en Fonction de l'Orientation du Vecteur d'Onde dans un Monocristal de Phosphite de Lithium, LiH2PO3
Authors: Beys Louis , Hillaire Paul
Published: May 2005

Using the relations between nonlinear optical coefficients and Raman scattering efficiencies of LO and TO phonons in LiH2PO3 single crystal, numerical values of d31 and d32 coefficients, in relative units, have been determined. The variations of the Raman scattering efficiencies have been studied with the wave vector k rotating in the xOz and the yOz planes. Theory and experiment are found to be in good agreement.
Etude des Vibrations SN et SO des Dérives de L'acide Imidodisulfurique par Spectrométrie Raman
Authors: Parent Y. , Semmoud A. , Iskander B. , Vast Et P. , Dele‐Dubois M. L. , Lorriaux‐Rubbens Et A. , Narula S. P.
Published: May 2005

The Raman spectra of sixteen compounds derived from HN(SO3)22− have been compared. The results show that the substitution of one or more of the oxygens of the original tetrahedron SO42− by a ligand F, Cl, NH, N, implies a contraction of the free SO bonds. This is characterized by the shifting of the symmetrical stretching frequency νs(SO). The polarizing power of the associated cations can also affect νs(SO).
Pressure and temperature dependence of the vibrational excitations of crystalline iodoform
Authors: Medina J. , Sherman W. F. , Wilkinson G. R.
Published: May 2005

Raman spectra of single crystals of iodoform have been investigated over the temperature range 10–300 K and under hydrostatic pressure up to 14 kbar. The pressure‐induced shifts in vibrational frequency of many different modes have been used to calculate their respective Gruneisen parameters γ which are found to vary both with the frequency and pressure. They are much greater for the intermolecular modes than for the internal modes. The infrared absorption spectra have also been observed at different temperatures and are used together with the Raman data to obtain dν/dT for each band. Some new infrared assignments are suggested.
Relaxation of molecular motions in dibromomethane by Raman band shape analysis
Authors: Prakash R. , Thyagarajan G.
Published: May 2005

Molecular vibrational and reorientational relaxation studies on CH2Br2 are presented using Raman band contours of ν3 (CBr symmetric stretch) and ν4 (BrCBr symmetric bend) bands. Fourier transforms of isotropic and anisotropic parts of the bands were employed to obtain correlation functions and correlation times. The results are compared with those reported previously and discussed in the light of the existing theories.
The vibrational spectra and structure of B6H62− and 1, 6‐C2B4H6
Authors: Bragin J. , Urevig D. S. , Diem M.
Published: May 2005

The infrared and Raman spectra of the cesium and tetramethylammonium salts of the hexahydro‐clovohexaborate dianion (B6H62−) are reported and the vibrational fundamentals assigned in detail. An analysis of the fundamental vibrations of this dianion and the isoelectronic carborane, 1, 6‐C2B4H6, shows the latter to have stronger BH and BB bonds.
Determination of Raman intensities of lattice vibrations in crystalline oxamide
Authors: Bleckmann P. , Thibud M.
Published: May 2005

Quantum‐chemical methods have been used for the calculation of the intensities of Raman‐active lattice vibrations in crystalline oxamide. In a first step, the frequencies and eigenvectors of the external vibrations in oxamide are calculated by use of the concept of a flexible vibrating molecule within the intermolecular atom‐atom forces. The interactions between macroscopic electric fields and external modes are discussed. The quantum‐mechanical aspects are considered and finally, a semiempirical method is extended to cover the relative Raman intensities of the external modes.
Vibrational spectrum and conformation of cyclopropyldimethylborane
Authors: Odom J. D. , Saari S. V. , Nease A. B. , Szafran Z. , Durig J. R.
Published: May 2005

The infrared (3500–50 cm−1) and Raman spectra (3500‐10 cm−1) have been recorded for cyclopropyldimethylborane in both the gaseous and solid states. Additionally, the Raman spectrum of the liquid was recorded and qualitative depolarization values were obtained. Only one conformation has been found in all three physical states and, on the basis of the polarized nature of the Raman band assigned as the BC2 antisymmetric stretch, this conformer is identified as being the bisected structure with Cs molecular symmetry. A complete vibrational assignment, except for the BC2 and two methyl torsional modes, is proposed based on the depolarization data, infrared gas phase band contours, and group frequencies. These results are compared to the corresponding data for several other organoboranes.
Raman spectra of Na3AsS4·8(D, H)2O and Na3SbS4·9(D, H)2O and OD(H)…S bonds in salt hydrates
Authors: Mikenda W. , Steidl H. , Preisinger A.
Published: May 2005

Raman spectra, measured in the temperature range T =75–295 K, are reported for H2O, D2O and isotopically dilute samples of Na3AsS4·8(D, H)2O and Na3SbS4·9(D, H)2O. At T =75 K the uncoupled OD(H) stretching frequencies are observed in the range ν = 2433–2664(3279–3618) cm−1 and ν = 2461–2528(3318–3417) cm−1 for the thioarsenate and the thioantimonate, respectively. Plausible assignments to the distinct crystallographically non‐equivalent OD(H) groups are given.

The correlation between the uncoupled OD stretching frequencies and the hydrogen bond distances R(D…S) of approximately linear OD…S bonds in salt hydrates is discussed. The frequency shifts upon H‐bond formation are shown to depend strongly on the chemical nature of the sulphur proton acceptors.
A Raman study of aqueous solutions of ferric nitrate, ferrous chloride and ferric chloride in the glassy state
Authors: Kanno H. , Hiraishi J.
Published: May 2005

Raman spectra have been obtained for aqueous solutions of Fe(NO3)3, FeCl2 and FeCl3 in the glassy state where R = moles of water/moles of salt = 10–20. The predominant jonic species in these solutions are [Fe(H2O)6]3+, [Fe(H2O)6]2+ and trans‐ [Fecl2(H2O)4]+, respectively. The second dominant ferric species in the glassy FeCl3 solution (R = 20) seems to be the [FeCl(H2O)5]2+ ion, which is inferred from comparison of the frequencies of the FeOH2 stretching Raman bands.
Etude, par Spectroscopie de Vibration Infrarouge et Raman, du Dihydrate de l'Acide Perchlorique dans les Etats Désordonnés: Verre et Liquide
Authors: Thi Mai Pham , Herzog‐Cance Marie‐Héléne , Potier Antoine , Potier Jacqueline
Published: May 2005

The infrared and Raman spectra of the mixture HClO4 · 2H2O in the glassy and liquid states have been investigated. Two species have been characterized:

the dioxonium perehlorate where the H5O2+ and ClO4− ions are linked by hydrogen bonds weaker than in the crystal (νOH(H5O2+) = 3430 and 3460 cm−1 respectively in the glass and liquid state Raman spectra and 3340 cm−1 for the crystal).

an ionic association, O3ClO−…H(OH)HOH2+, in which the vibrational motions of the terminal H2O molecules are characterized by δOH = 1530 and 1550 cm−1 and νOH = 3480 and 3520 cm−1 respectively in the glass and liquid state Raman spectra and in which ν1(ClO4−) shifts to lower frequencies (Δν = −12cm−1).
Raman linewidth study of rotational motion of chloroform in aqueous solution
Authors: Tanabe Kazutoshi
Published: May 2005

Isotropic and anisotropic Raman linewidths of the CD stretching mode of chloroform‐d have been measured in water and other solvents, and rotational diffusion constants for the rocking motion of chloroform molecules around their perpendicular to the symmetry axis have been determined from linewidths. The correlation of experimental rotational diffusion constants in solutions, with fluidities of solvents, is examined, and the effect of iceberg structures formed around chloroform molecules in aqueous solution on the rotational motion of chloroform is discussed.
Torsionally induced bands in the Raman spectrum of a biphenyl crystal
Authors: Bree A. , Zwarich R.
Published: May 2005

Three broad bands at 166, 410 and 836 cm−1 in the (c*c*) polarized Raman spectrum of a biphenyl crystal are ascribed to B2u5 Au and Au fundamentals, respectively, which are weakly Raman active in molecules that have about ten quanta of the central bond torsion. The intensities of these broad lines diminish as the temperature is lowered, and the number of molecules with sufficient torsional quanta to induce the transitions declines. Near degeneracies are located at 410 and 840 cm−1 between Au and B3g and Au and B1g fundamentals, respectively.