bluuebunny/crossref_metadata_2025_split huggingface dataset:
Raman spectra of halogen‐substituted methanes in the liquid state. 3—Temperature effects
Authors: Fukushi Kohji , Fukuda Takuya , Kimura Masao 
Published: May 2005

AbstractThe effect of temperature on the peak positions, the isotropic and reorientational band widths and the depolarization ratios of the Raman bands for the totally symmetric vibrations of CHCl3, CH2Cl2, CH2Br2, CH3Br, CH3I and CD3I has been measured in the liquid state. The isotropic band width for a CX stretching vibration decreases with increasing temperature for molecule with only one CX bond, whereas it increases for a molecule with two or three equivalent CX bonds. The isotropic band width for the deformation vibrations decreases with increase in temperature. For all the bands, the depolarization ratios depend only slightly on temperature.
Raman and Fourier transform infrared study of yeast alcohol dehydrogenase
Authors: Hall William H. , Jagodzinski Paul W. 
Published: May 2005

AbstractRaman spectra of yeast alcohol dehydrogenase in buffered, aqueous solutions and in D2O, and FTIR spectra of aqueous solutions and thin films have been collected and analyzed. No significant differences between the Raman spectra in the pH range 6.00–7.50 and between the infrared spectra of the solution and film have been observed. The tyrosine doublet strongly favors exposed hydroxyl groups and the Raman spectra indicate multiple conformations for the disulfide moieties. Analysis of Raman intensities favors significant α‐helix and random coil contents. The secondary structure of yeast alcohol dehydrogenase based on Raman data is compared with the better characterized secondary structure of equine liver alcohol dehydrogenase.
Etude du Polypropylègne Isotactique par Effet Raman‐Laser: Déformation par Etirage Uniaxial
Authors: Cambon L. D. , Ramonja J. L. , Luu D. V. 
Published: May 2005

AbstractL'étude par effet Raman‐laser d'échantillons de polypropylène isotactique, étirés soit à température ambiante, soit à 135°C par la méthode d'extrusion‐soufflage, nous permet de suivre l'évolution des phases au cours de la déformation. Nos résultats montrent d'une part, que la phase amorphe se déforme en premier, entraǐnant l'orientation de la phase cristalline dans la direction de l'axe d'etirage, d'autre part que cette měme phase amorphe a tendance à se concentrer dans le plan perpendiculaire à l'axe d'étirage.
Raman spectra of intraocular lenses before and after implantation in relation to their biocompatibility
Authors: Bertoluzza A. , Fagnano C. , Monti P. , Semerano G. , Garcia‐Ramos J. V. , Caramazza R. , Cellini M. 
Published: May 2005

AbstractRaman spectra of seven commercial poly(methyl methacrylate) intraocular lenses (IOLs) before and after implantation in the anterior chamber of rabbit eyes are reported and discussed in order to assess their biocompatibility.The material does not seem to change its structure on implantation; in particular the level of residual monomer, which is the main factor responsible for the biological intolerance of the lenses, remains constant.Providing a non‐destructive structural probe, Raman spectroscopy is a suitable method for monitoring the biocompatibility of ophthalmological materials.
Raman optical activity of some azo dyes induced by inclusion in cyclodextrins
Authors: Hattori T. , Higuchi S. , Tanaka S. 
Published: May 2005

AbstractThe Raman optical activity (ROA) spectra of some azo dyes binding to cyclodextrins have been measured. This appears to be the first successful attempt to measure the ROA induced in achiral molecules by intermolecular interaction with chiral molecules. There was no relationship between the ROA signals and the Raman shifts accompanying inclusion phenomenon. From comparison of the ROA spectra of methyl orange with α‐cyclodextrin and congo red with γ‐cyclodextrin, it seems that the ROA spectra reflect the difference in the positions of the SO3− groups in the guest molecules.
Etude par Spectrometrie Raman de Monocristaux de CdMo6Cl14 et CdMo6Br14
Authors: Mancour S. Mancour , Caillet P. , Jouan M. , Dao Nguyen Quy 
Published: May 2005

AbstractRaman spectra of single crystals of CdMo6Cl14 and CdMo6Br14 were recorded with several directions of polarization. It is shown that the spectra must be interpreted from one [Mo6X8i]X6a cluster, slightly distorted apart cubic ideal symmetry. All the vibrational modes are identified and their frequencies determined. This work is the first Raman study of ‘cube‐octahedral’ cluster Mo6X8 in the solid state.
Resonance Raman spectra of 2‐(2‐pyridylazo)‐5‐diethylaminophenol and its complex at various pH values
Authors: Kawai Kiyoyasu , Masago Harue , Kanamori Kan , Kanesaka Isao , Kasahara Issei , Goto Katsumi 
Published: May 2005

AbstractThe structure of 2‐(2‐pyridylazo)‐5‐diethylaminophenol (PADAP) and its complex at various pH values was studied by resonance Raman spectroscopy. The spectral features are sensitive to the pH and the solvent, which can be explained in terms of azo–hydrazone tautomers. Two types of quinonoid structures are found under neutral conditions: a hydrazone structure in chloroform solution and a pyridone‐like structure with an NH bond in the pyridine ring in aqueous solution. The quinoid structure is found at both pH 0.1 and 2.3. The relationship between the structure and the absorption spectrum under neutral conditions is discussed on the basis of CNDO/2 calculations.
Characterization of the flavin–protein interaction in L‐Lactate oxidase and old yellow enzyme by resonance inverse Raman spectroscopy
Authors: Bienstock Rachelle J. , Schopfer Lawrence M. , Morris Michael D. 
Published: May 2005

AbstractResonance inverse Raman spectroscopy was used to examine the interactions between the flavin and surounding protein in L‐lactate oxidase (from Mycobacterium smegmatis) and Old Yellow Enzyme (from brewer's bottom yeast). Spectra were taken of the enzymes both free and bound to various ligands. For L‐lactate oxidase, the ligands consisted of substrate analogs (acetate, propionate) and inorganic anions (phosphate, sulfate and nitrate). For the inorganic anions, the expected attenuation with detuning was not observed for several bands which are associated with flavin rings II and III. This effect appears to be due to a disruption of ring stacking between the uracil–pyrazine end of the flavin moiety and an aromatic amino acid. A shift in the 1232 cm−1 band and changes in the bandwidths of bands in the 1450–1600 cm−1 region indicate minor reorganization of the hydrogen bonding structure around the isoalloxazine on ligand binding.For Old Yellow Enzyme, the ligand was chloride. Chloride caused a slight change to the Raman spectrum, indicative of decreased hydrogen bonding to the flavin.
Le Système Gazeux Gallium–Chlore: Etude par Spectrométrie Raman. 2–Analyse Quantitative
Authors: Hillel R. , Aǐt‐Hou A. , Berthet M. P. , Bouix J. 
Published: May 2005

AbstractProcedures for the quantitative treatment of Raman spectra are proposed for the investigation of gallium–chlorine gaseous mixtures. They are based on correlations between pressures and Raman band intensities and require a knowledge of reliable entropy and heat capacity data for the main gaseous species. For the ratio Cl/Ga=3 and between 590 and 690 K, the pressure determinations from the band intensity evolution corresponding to the symmetric vibrational modes ‘ν1’ of Ga2Cl6 and GaCl3 confirm the starting consideration of the single equilibrium Ga2Cl6(g)⇌2GaCl3(g). They lead to an enthalpy of dissociation of Ga2Cl6 very close to the literature data. For Cl/Ga3 and between 800 and 950 K, the treatment of the Raman spectra is performed by computation of the GaCl spectrum in order to discriminate between the GaCl3 ‘ν1’ band intensity and the GaCl ‘νs’ branch intensity. This intensity difference and the GaCl ‘νQ’ branch intensity are used for pressure determinations. The results are consistent with the proposed equilibrium 2Ga(l)+GaCl3(g)⇌3GaCl(g). They lead to a calculated reaction enthalpy that allow one to select a reliable value for the enthalpy of formation of GaCl.
UV resonance Raman excitation profiles of l‐cystine
Authors: Johnson Craig R. , Asher Sanford A. 
Published: May 2005

AbstractThe UV Raman excitation profiles of l‐cystine have been measured between 220 and 514.5 nm. No enhancement is observed from the lowest energy electronic transition (λmax = 245 nm). The excitation profiles for the SS, CS and CO stretching vibrations are each satisfactorily modeled by standard Albrecht A‐term pre‐resonance expressions which indicate that the Raman intensities derive from a state(s) at ca 170 nm which is probably σ → σ* in character. Selective enhancement of disulfide stretching vibrations in proteins will require excitation in the vacuum UV spectral region.
Fourier transform infrared and laser Raman microprobe spectra of uridine
Authors: Xu Zhen H. , Butler Ian S. 
Published: May 2005

AbstractVibrational assignments are proposed for the room‐temperature FTIR and laser Raman microprobe spectra of solid uridine. These assignments are based chiefly on comparisons of the vibrational data observed for uracil, D‐ribose and a 1:1 mixture of these two compounds with those for the uridine nucleoside itself.
Raman spectral studies of single crystal CH3ND3NO3
Authors: Mylrajan M. , Srinivasan T. K. K. 
Published: May 2005

AbstractRaman spectra of single crystal N‐deuterated methylammonium nitrate (CH3ND3NO3) were studied in the temperature range 77–400 K. A systematic temperature dependence study of the internal and external modes was carried out. The results show the preseuce of three structural phases. Raman spectra of phase II in the internal and lattice region were interpreted on the basis of a D space group and relative polarization data. A thermal hysteresis characteristic of a first‐order transition was observed in the
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The spectral features of phase I indicate this to be a plastic phase, in which cations and anions exhibit isotropic reorientational motion. The spectral changes that occur in the
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transition suggest a freezing out of the thermal motion and reveal that only minor changes are involved in this transition.
Application of transform theory to resonance cars excitation profiles of a cyanine dye
Authors: Watanabe Nobuhisa , Shimizu Masaaki , Tanaka Jiro 
Published: May 2005

AbstractThe transform method has been used to investigate the CARS excitation profiles (CEPs) of a highly fluorescent cyanine dye including linear non‐Condon sources of scattering. It is demonstrated that the calculated predictions of the CEPs are in good agreement with the experimental data of the CARS excitation profile of the dye. The observed values of the linear non‐Condon activity parameters, Ca, of three vibrational modes of 3,3′‐diethylthiacar‐bocyanine bromide were as large as 0.3. This suggests that linear non‐Condon electronic transition moments are important in the investigation of CEPs of cyanine dyes.
Surface‐enhanced raman spectroscopy of acrylamide and polyacrylamide adsorbed on silver colloid surfaces: Polymerization of acrylamide on silver
Authors: Suh J. S. , Michaelian K. H. 
Published: May 2005

AbstractThe SERS spectra of acrylamide and polyacrylamide adsorbed on the surface of silver colloid particles are reported. The SERS spectrum of acrylamide is interpreted as indicating that polymerization takes place on silver colloid surfaces. Evidence supporting this conclusion includes the fact that the CH2 stretching vibrations of acrylamide adsorbed on the silver colloid surfaces are at 2926 and 2972 cm−1, which correspond exactly to those of polyacrylamide, and are greatly different from those at 3050 and 3115 cm−1 observed for acrylamide in aqueous solution. Another possible indication of polymerization is the band at 1164 cm−1, which can be assigned to a polymer skeletal vibration.Although acrylamide is polymerized on the silver colloid surfaces, the SERS spectra of polyacrylamide polymerized before adsorption and acrylamide polymerized on the colloid surface are very different from each other. This observation is attributed to the different surface geometry of these two polymers, and the possible contibution of non‐polymerized species in the SERS spectrum of acrylamide.
Resonance Raman spectra of the N,N ‐ dihydro‐4,4′‐bipyridinium radical cation
Authors: Barker David J. , Cooney Ralph P. , Summers Lindsay A. 
Published: May 2005

AbstractThe Raman spectrum of diprotonated 4,4′‐bipyridine in the solid state as the dibromide salt is reported. The resonance Raman spectrum of the radical cation derived by one‐electron reduction of the dication is also reported. Viscous glycerol was employed as a solvent in order to protect the radical by inhibiting oxygen diffusion. The spectra are interpreted on the basis of a comparison with those of related compounds. A large shift in frequency (+70 cm−1) of the inter‐ring stretching vibration between the parent dication and radical monocation is observed. This has been interpreted in terms of a major contribution to the delocalized radical structure of a quinoid‐type form.
Spectres Raman de l'Ethylene‐d0 et de l'Ethylene‐d4 en phase Gazeuse. 1–Etude des Contours des Bandes ν6 et ν8 et Evaluation de la Constante de Coriolis, ζ,8
Authors: Barbès H. 
Published: May 2005

AbstractLes structures rotationnelles des bandes Raman ν6 et ν8 de l'éthylène‐d0 et de l'éthylène‐d4 à l'état gazeux ont été enregistrées. Le contour de chaque bande perturbée ν8 a été analysé en simulant les bandes du rotateur asymétrique, ce qui a permis de mettre en évidence les effects d'une interaction de Coriolis de type a. La constante de Coriolis, ζ,8 a été déduite pour chaque molécule.
Raman spectra of single‐crystal Cd(BrO3)2 · 2H2O and polycrystalline Cd(BrO3)2 · 2D2O
Authors: Devananthan T. , Srinivasan T. K. K. 
Published: May 2005

AbstractRaman spectra of single‐crystal Cd(BrO3)2 · 2H2O and polycrystalline hydrate, deuterate and partially deuterated samples at 90 and 298 K were investigated in detail. Polycrystalline hydrate, deuterate and partially deuterated samples were examined at 90 and 298 K in the OH and OD internal region by infrared spectroscopy in order to explore the structural environment of water of hydration. Vibrations in the OH stretching region were attributed to (H2O)I and (H2O)II type molecules. Single‐crystal Raman spectra were analysed and most of the normal modes were assigned.
Measurement of Raman scattered intensities in media with natural or field‐induced optical activity
Authors: Slobodyanyuk A. V. , Schaack G. 
Published: May 2005

AbstractThe intensity of Raman scattered light has been calculated for gyrotropic media, i.e. for media with a natural optical activity or a gyrotropy induced by a magnetic field. It is shown that anomalies in the scattered intensity are in general due to interference effects between the two orthogonally polarized normal modes of electromagnetic radiation propagating in the anisotropic crystal either in the incident or in the scattered beam or in both. Only when the state of polarization of the incident and the scattered waves agrees with one of these normal modes are clear results obtained which are simply to interpret. Hence the intensity anomalies sometimes observed in these media find an interpretation in the frame of the generally accepted theory. No breakdown of selection rules will occur in such media.The calculated results are compared with experimental findings in α‐quartz and in ZnP2 and also in paramagnetic TmVO4 and in CeF3 in external magnetic fields.
Spectra and structure of small ring compounds. XLIX—Raman and infrared spectra, conformational analysis and vibrational assignment of methylcyclobutane and methyl‐d3‐cyclobutane
Authors: Kalasinsky V. F. , Harris W. C. , Holtzclaw P. W. , Little T. S. , Geyer T. J. , Durig J. R. 
Published: May 2005

AbstractThe Raman (3500–20 cm−1) and infrared (3500–50 cm−1) spectra of gaseous and solid methylcyclobutane and methyl‐d3‐cyclobutane have been recorded. Additionally, the Raman spectra of the pure liquids have been recorded and qualitative depolarization values have been obtained. The spectra have been interpreted on the basis that both the axial and equatorial conformers are present in the fluid phases and that the equatorial form is thermodynamically preferred and the only form present in the annealed solid. All 39 of the normal vibrational modes have been assigned for both the d0 and d3 compounds. An abundance of spectral evidence is presented which indicates extensive coupling between the vibrations associated with the ring and those of the methyl group. The CH3 internal torsional mode has been observed in the Raman spectrum of the solid at 232 cm−1 and utilizing this frequency the periodic threefold barrier to internal rotation has been calculated to be 1190 cm−1 (3.40 kcal mol−1). The fundamental ring puckering mode has been assigned from the Raman spectra of the gases to weak features observed at 161 and 154 cm−1 for the d0 and d3 compounds, respectively. All of these results are compared with the corresponding quantities for some similar molecules.
Vibrational spectroscopy at very high pressures. 47—Raman scattering study of K3Cu(CN)4: A trigonally distorted species
Authors: Adams David M. , Hatton Peter D. 
Published: May 2005

AbstractK3Cu(CN)4 displays a high‐pressure phase transition at 14 kbar and another at ca 100 kbar (as estimated visually using an ungasketted diamond anvil cell). No Raman spectra could be obtained for phase III but the Raman spectra of phase II show that the trigonal distortion evident at ambient pressures is retained. The suggested space group of phase II is C, a maximal zellengleich descent of the ambient structure, C. As with K2M(CN)4 (M = Zn, Cd or Hg), a trigonal distortion appears favoured under external pressure.
Calculation of the Raman line broadening on carbonation in synthetic hydroxyapatite
Authors: de Mul F. F. M. , Otto C. , Greve J. , Arends J. , Ten Bosch J. J. 
Published: May 2005

AbstractThe position and broadening of the Raman band associated with the phosphate symmetric stretching vibration in hydroxyapatite are simulated using a simple inter‐ and intra‐ionic potential. The results are compared with experimental values. This comparison was made as a function of the incorporation of carbonate ions in the lattice for a number of substitution models. The line width of the phosphate symmetric stretching vibration is shown both theoretically and experimentally to be dependent on the carbonate content. Good agreement between calculations and experiment is obtained. The results of the calculations offer some support to the suggestions in the literature that the dielectric constant has to be considered as a function of the distance in the lattice, increasing beyond the first environmental layer.
A test reaction for rapid‐mixing, rapid‐flow Raman cells
Authors: Cartier L. R. Sans , Storer A. C. , Carey P. R. 
Published: May 2005

AbstractThe design and construction of a four‐jet rapid‐mixing, rapid‐flow Raman cell, suitable for following chemical or biochemical reaction events 20 ms and longer after mixing, is described. A suitable test reaction, the base‐catalysed hydrolysis of 2,4‐dinitrophenyl acetate in 10% methanol, has been characterized by a stopped‐flow kinetic analysis. When this reaction is carried out in the rapid‐mixing, rapid‐flow Raman cell a resonance Raman peak of the 2,4‐dinitrophenolate product, measured against a methanol peak as an internal standard, permits the calculation of the extent of product formation. Using the rate constant determined from the stopped‐flow kinetic analysis, the dead time (the time after mixing) in the Raman flow cell can be calculated for the flow‐rate employed. When the flow system is operating correctly, this dead time is in close agreement with that calculated from the known flow‐rate and the combined volume of the mixing and flow cell. Since the reaction is monitored using the commonly available 457.9 nm Ar+ line, it can be used to test the operational efficiency of rapid‐mixing, rapid‐flow systems built in most Raman laboratories.
Phase transitions in non‐ionic surfactant–water systems as studied by Raman spectrometry. II—A new methodology
Authors: Gaufrès R. , Bribes J.‐L. , Sportouch S. , Ammour J. , Maillols J. 
Published: May 2005

AbstractIn order to compare the molecular Raman spectra between an optically isotropic phase and an anisotropic phase, a method is proposed having especially in view the study of transitions in lyotropic surfactant systems. Its application to the transition between the isotropic and hexagonal phases in the water‐α‐octyl‐ω‐hydroxypentakis (oxyethylene) system shows that there is no significant molecular structure change at transition. This result suggests that all the micelles in the L1 phase in equilibrium with the hexagonal phase have a cylindrical shape.
Solid‐state vibrational spectroscopy of disordered crystals. II—Phonon spectra and structure of crystalline thioanisole
Authors: Cataliotti Rosario Sergio , Paliani Giulio , Santini Sergio 
Published: May 2005

AbstractThe phonon spectra of thioanisole have been measured in a temperature range from the freezing point to 77 K, in order to ascertain if disordered crystalline phases are obtained as in other sulphur‐containing molecular crystals studied. All the Davidov splitting components have been assigned on the basis of a correlation diagram which has been constructed assuming a unit cell isomorphous with a Cmc21 orthorhombic crystal.
High‐pressure Raman study of liquid and solid thiophene up to 100 kbar at 300 K
Authors: Shimizu H. , Matsunami N. 
Published: May 2005

AbstractHigh‐pressure Raman spectra of liquid and solid thiophene C4H4S have been measured up to 100 kbar at 300 K in a gasketed diamond anvil cell. The pressure dependence of intramolecular and intermolecular vibrational modes revealed a solidification point at 6 kbar and a pressure‐induced phase transition at 40 kbar. This solid‐solid phase transition was identified as the III→IV phase transition by comparison with the intermolecular Raman spectra of the low‐temperature solids at atmospheric pressure. The appearance of a dark‐red modification of C4H4S, which is irreversibly formed at pressures above 80 kbar with laser irradiation, is discussed.
Resonance Raman studies of the structures and vibrational assignments of photochromic S‐alkyldithizones
Authors: Takahashi Hiroaki , Yamada Osamu , Isaka Hiroaki , Igarashi Takashi , Kaneko Norio 
Published: May 2005

AbstractThe resonance Raman spectra of S‐methyldithizone (MeHDz), S‐ethyldithizone (EtHDz) and S‐isopropyldithizone (iPrHDz) have been measured in the solid state and in solution. It is shown that the red and yellow isomers of these S‐alkyldithizones adopt in solution the trans‐syn‐s‐trans and trans‐anti‐s‐trans configurations, respectively, with respect to the NN, CN and CN bonds of the formazan skeleton. It is also demonstrated that for EtHDz the red and yellow isomers can be isolated as different crystal forms. Vibrational assignments are given for both red and yellow isomers of MeHDz based on the frequency shifts of five kinds of isotopically substituted species.
Raman spectra of single crystals of α‐P4S3
Authors: Burns Gary R. , Rollo Joanne R. , Syme Roderick W. G. 
Published: May 2005

AbstractPolarization data for the Raman‐active k = 0 phonons of single crystals of α‐P4S3 have been measured at 10 K and at high resolution. Of the 24 external and 60 internal phonons expected for the D2h factor group of α‐P4S3 we have observed 16 external and 38 internal phonons. The effect of the layer lattice has been proposed to explain the absence of some expected phonon structure. The present work together with an earlier study of the pressure and temperature dependence of the Raman‐active phonons have enabled the 4A1, A2 and 5E internal molecular modes to be assigned. The resulting normal coordinates give good fits for the Raman‐active bands of the heavy isotope P4 32S2 34S and for the mixed chalcogen species P4S3 − xSex.