bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polarized Raman spectrum and normal coordinate analysis of α‐MnMoO4
Authors: Kanesaka Isao , Hashiba Hideto , Matsuura Ikuya 
Published: May 2005

AbstractThe poarized Raman spectum of α‐MnMoO4 and the infrared spectrum of the poycrystalline material are reported. The observed bands were assigned on the basis of a normal coordinate analysis using a valences force field. Force constants of molybdate ions were examined in detail. Lattic vibrations are explained mainly in terms of MnO streching force constants. Coupling between MoO stretchings on MoO bonds of differents lengths is slight and in general a v2‐like mode is higher in frequesncy than a v4‐like mode. The position of oxygen atoms substituted after an oxidation reaction of an olefin by using an 18O tracer is identified.
Symmetries of SF6 and CO2 in liquid and high‐pressure gaseous states
Authors: Bhattacharjee R. 
Published: May 2005

AbstractThe theory of distortion‐induced activity (DIA) of IR and Raman forbidden modes has been applied to SF6 and CO2 in the liquid and high‐pressure gaseous states. It is concluded that these molecules attain polar types of distortions in these states.
Etude par Spectrométrie Infrarouge et Raman des Phases Cristallines Basses Temperatures de (NH4)3H(SO4)2
Authors: Kamoun M. , Lautié A. , Romain F. , Novak A. 
Published: May 2005

AbstractThe Raman and infrared spectra of (NH4)3H(SO4)2 crystal were investigated in the range 20–300 K. An assignment of bands due to internal and external vibrations is given. The crystalline phases designated II, III, V and VII were identified and characterized spectroscopically. Hydrogen bonding, the nature and degree of structural (dis)order and the mechanisms of the phase transitions are discussed. The NH4+ ions show an important orientational disorder and become fully ordered in phase VII only. They are involved in all transitions and seem the main cause of the ferroelectricity at low temperature.
Determination of potential curve parameters of excited electronic states of polyatomic molecules by resonance CARS
Authors: Lau A. , Pfeiffer M. , Werncke W. , Weigmann H.‐J. , Lenz K. 
Published: May 2005

AbstractResonance CARS line‐shape analysis has been applied to determine the parameters of the excited electronic state potential curves of a cyanine dye and its short‐lived photoisomers during the process of photoisomerization. For this very complicated situation other methods for the estimation of these values would fail. The origin shift parameters determined are very small and the homogeneous line width is smaller than the line width of the absorption band.
Spectroscopic and calorimetric studies of phospholipid–polyamine molecular interactions
Authors: Bertoluzza A. , Bonora S. , Fini G. , Morelli M. A. 
Published: May 2005

AbstractThe effect of polyamines (putrescine, spermine and spermidine) on the physical properties of liposomes of phospholipids with different amount of charge on the bilayer was studied. The measured effect depends both on the charge of the lipid and on the charge of the polyamine, which under physiological conditions can be considered as a polycation. No interaction was observed with a neutral phospholipid for all the polyamines considered. With charged phospholipids, polyamines modify the surface charge and, as a consequence, the inner structure of the core of the bilayer also changes. The polyamine with the highest positive charge and the phospholipid with the highest content of negative groups showed the strongest interaction.
Infrared and single‐crystal Raman spectra of (NH4)3H(SO4)2
Authors: Rajagopal P. , Aruldhas G. 
Published: May 2005

AbstractInfrared and polarized Raman spectra of (NH4)3H(SO4)2 have been recorded and analysed. Multiple bands are observed for the vibrational modes of SO and NH groups. HSO and SO ions are found to coexist with vibrational interaction between them. NH ion is not rotating freely in the lattice.
Calculation of the vibration–rotation line intensities in the Raman spectra of gases
Authors: Cheglokov A. E. , Ulenikov O. N. , Cherepanov V. N. , Makushkin Yu. S. 
Published: May 2005

AbstractThe method of irreducible tensorial sets is used for deriving general formulae describing the intensities of vibration‐rotation Raman lines of molecules of different symmetries. Using this method, generalization of the parameters characterizing isotropic, antisymmetric scattering, taking into account vibration‐rotation interactions, has been carried out. The effect of vibration‐rotation interactions on the Raman scattering cross‐section is considered.
SERS of α, β‐unsaturated ketones on colloidal silver
Authors: Clavijo R. E. , Mutus B. , Aroca R. , Dimmock J. R. , Phillips O. A. 
Published: May 2005

AbstractRaman and infrared spectra of four α,β‐unsaturated ketones were studied. Surface‐enhanced Raman spectra were obtained on colloidal silver with two laser lines (514.5 and 647.1 nm). Evidence of strong chemisorption on the silver surface was supported by the observation of the metal‐ligand stretching vibrations. Molecular orientation of the substrate is discussed using the electromagnetic interpretation of observed intensities.
Vibroelectronic transitions in a geological fluorapatite (Esparraguina)
Authors: Martin F. , Prieto A. C. , Martin I. , Rull F. 
Published: May 2005

AbstractA Raman study of a geological fluorapatite with significant substitutions of Ca2+ by Sr2+ and Ce3+ and some other minor impurities is reported. The spectra were measured at 10 K and at room temperature using excitation wavelengths of 488, 514.5 and 647.1 nm. Strong vibroelectronic transitions were observed and are explained in terms of the role played by the impurities.
Resonance Raman spectra of a Langmuir–Blodgett film of substituted copper phthalocyanine on n‐type silicon
Authors: McConnell A. A. , Smith W. E. 
Published: May 2005

AbstractResonance Raman excitation profiles for a substituted phthalocyanine dispersed as a polycrystalline powder in a silver disc were compared with those for a Langmuir–Blodgett (LB) multilayer of the same material on a silicon surface. There is a strong angular dependence of the efficiency of the scattering process. The LB profiles are strongly influenced by the electronic fields from the smooth semiconducting silicon surface, which gives rise to increased π‐π* energy separation and comparatively efficient scattering from upper vibronic states.
Concentration (D2O in H2O) and temperature Raman study of the molecular interactions in the OD stretching spectra of D2O and D2O/H2O mixtures using the fourier deconvolution technique
Authors: Zhelyaskov V. , Georgiev G. , Nickolov Zh. , Miteva M. 
Published: May 2005

AbstractThe OD stretching spectra of D2O for temperatures from 5 to 90°C and for concentrations (D2O in H2O) from 100 to 10 mol‐% were studied. These spectra were treated by means of the Fourier deconvolution technique for the first time.Using the positions of the resolved components the coupling constants for intra‐ and inter‐molecular and Fermi resonance interactions and all parameters according to the presented model, for all investigated temperatures, were evaluated. A gradual decrease in all interactions was observed in the concentration study, in accordance with expectations and in agreement with the results for dilute solutions of H2O in D2O.The temperature behaviour of the coupling constants and other parameters were in accordance with the corresponding data for H2O. The only exception is the temperature behaviour of the intramolecular coupling constant. The greater mass of the D atom is one of the probable reasons that lead to the smaller sensitivity of OD frequency to the hydrogen bond fluctuations.All the results verify the assignments and assumptions made according to the model presented and support the continuous model for the water structure.
Raman spectroscopic study of chain complexes of bis(hydrazine) zine and manganese halides
Authors: Personette William , Szczepanski Jan , KuBulat Kulim , Vala Martin 
Published: May 2005

AbstractThe Raman spectra of polycrystalline Zn (N2H4)2X2 (X  Cl or Br) and Mn(N2H4)2Cl2 were run over the range 90–3590 cm−1. The bands observed in the higher frequency region (400–3590 cm−1) were assigned to perturbed hydrazine vibrations and generally agree well with previously reported infrared studies. A normal coordinate analysis was performed on the core of the complexes, metal · N4X2, and used to assign the observed metalnitrogen and metal–halide bands in the lower frequency range (90–400 cm−1).
Etude Raman des Verres 0.2Na2O(0.8x)SiO2xB2O3 (0<x⩽0.7)
Authors: Assih Toyi , Beys Louis , Hillaire Paul , Phalippou Jean 
Published: May 2005

AbstractL'étude Raman des verres de la série 0.2Na2O(0.8 − x)SiO2xB2O3 a été réalisée pour des pourcentages molaires x en B2O3 tels que 0 < x ⩽ 0.7. Le choix des échatillons est tel que la droite leurs points figuratifs dans le diagramme du ternaire, coupe celle qui délimite les zones relatives aux oxygénes pontants et non pontants, permettant ainsi d'observer: les modifications des bandes Raman caractéristiques des 4. Dans les spectres de basses fréquences, l'étude de la diffusion de la lumiére par les vibrations acoutiques, pondérée par l'effet de température, nous a permis en utilisant la théoprie de Martin et Brenig de déduire une ‘longueur de corrélation’ caractéristique de l'ordre à courte‐distance.
Etude par Microscopie Raman de la Couche Liquide Situee au Contact d'un Cristal de NaNO3 en Cours de Dissolution dans sa Solution Mère
Authors: Koussinsa F. , Bertin F. , Bouix J. 
Published: May 2005

AbstractThe efficiency of Raman microscopy coupled with multichannel acquisition of data was tested for studying the dissolution layer of a mineral salt in its undersaturated mother solution. Experimental work was carried out on sodium nitrate solutions at concentrations ranging between 0.05 and 7.8 M. At lower concentrations the existence of three main species, free aquated ions, solvent‐separated ion pairs and contact ion pairs, was confirmed spectroscopically, in addition to a small amount of aggregates (NO3− · Na+)n which occur only at high concentrations ([NO3−]>2 M). Gaussian‐Lorentzian parameters of each ν1(A′1) band characteristic of such individual species were calculated and were found to vary considerably depending on whether the Raman spectra were recorded with a standard scanning system or with a multichannel detector. When the laser beam was focused at the interface between a dissolving NaNO3 crystal and the sodium nitrate solution ([NO3−]=4.68 M), the micro‐Raman spectra showed that the concentration of aggregates was considerably increased compared with that determined in the same way in the bulk of the nitrate solution. The technique used to obtain reliable spectra of the dissolution layer is discussed in detail.
Vibrational spectra and conformations of chloro‐ and bromo‐cyclobutane
Authors: Gatial A. , Klaeboe P. , Nielsen C. J. , Powell D. L. , Sülzle D. , Kondow A. J. 
Published: May 2005

AbstractThe Raman and IR spectra of chloro‐ and bromo‐cyclobutane as vapours, liquids and as amorphous and crystalline solids were recorded at various temperatures. Additional IR spectra of the high‐pressure crystalline phases were obtained at ca 25 kbar pressure. IR matrix isolation spectra were recorded at 14 K, using the hot nozzle technique.Evidence is presented to show that chloro‐ and bromo‐cyclobutane have a second (axial) conformer existing in amounts less than 10% for chloro‐ and 3% for bromo‐cyclobutane at ambient temperature, in addition to the dominant (equatorial) conformer. From the study of the Raman spectra of the liquid and vapour as a function of temperature, enthalpy differences between the two conformers were calculated. The axial conformers could not be trapped at 17 K, revealing the barrier to ring conversion to be smaller than 5 kJ mol−1.New vibrational assignments, supported by normal coordinate analyses are presented for both compounds.
Normal coordinate analysis of p‐nitrobenzaldehyde and assignments of infrared and Raman bands
Authors: Mohan S. , Prabakaran A. R. 
Published: May 2005

AbstractThe infrared and Raman spectra of p‐nitrobenzaldehyde were recorded on a Perkin‐Elmer IR 983 double‐beam grating spectrophotometer and on a Cary Model 82 grating spectrophotometer, respectively. The observed frequencies were assigned to various modes of vibrations on the basis of normal coordinate calculations.
Raman intensities of cyclohexane in the gas phase
Authors: Lorenzo C. F. , Alcántara R. , Martin J. 
Published: May 2005

AbstractAn experimental study of the Raman intensities of cyclohexane in the gas phase is presented. The absolute scattering coefficients and depolarization ratios corresponding to clearly differentiated spectral regions (containing one or more normal modes) were measured. The absoulute intensity of the 802 cm−1 Raman line was used as an external intensity standard. The value of S obtained for this band is 12.24 × 10−81 C2V−2 m4.
Surface‐enhanced resonance Raman spectroscopy of sulphonated copper phthalocyanine at a silver electrode
Authors: McConnell A. A. , Nimmo J. A. , Smith W. E. 
Published: May 2005

AbstractThe Raman spectrum of sulphonated copper phthalocyanine on a silver electrode surface is reported for four excitation wavelengths in the Q‐band region at voltages between +0.6 and −0.6 V (vs SCE). SERS activity is observed and the bonding and orientation of the surface species are voltage dependent and are inferred from a vibrational analysis. Maximum scattering intensity is observed at −0.2 V (vs SCE) and is attributed to molecules bonded edge‐on to the surface through SO3− groups.
Fourier transform infrared and Raman microprobe spectra of some silylated ribonucleosides
Authors: Butler Ian S. , Xu Zhen H. , Ogilvie Kelvin K. 
Published: May 2005

AbstractThe FT‐IR and laser micro‐Raman spectra of ten silylated nucleoside derivatives of uridine and their synthetic precursors, tert‐butyldimethylsilyl chloride and monomethoxytrityl chloride, were measured at room temperature. Some spectral differences are clearly evident for the 2′‐ and 3′ ‐silylated isomers; such distinctions are difficult to observe by other spectroscopic methods (e.g. 1H NMR spectroscopy). The differences in the positions of the CO stretching vibrations for the uracil base in uridine and the silylated derivatives are due chiefly to variations in the extent of hydrogen bonding in the solids. In addition, several bands attributable to SiO modes in the silylated compounds have been assigned.
Raman spectra and phase transitions of (5‐dimethylaminopenta‐2, 4‐dienylidene)‐dimethylammonium perchlorate
Authors: Sano Norimichi , Shimizu Masaaki , Tanaka Jiro 
Published: May 2005

AbstractLattice vibrational Raman spectra of (5‐dimethylaminopenta‐2, 4‐dienylidene)dimethylammonium perchlorate were measured for two crystal modifications at various temperatures. The phonon frequencies below 200 cm−1 were different for the two crystal forms. A phase transition was found by means of Raman spectra and differential scanning calorimetry (DSC). With increase in temperature of the crystal, the orange form is converted to the yellow form at ca. 370 K, and this transition is irreversible. Near the transition temperature, the Raman bands of both forms were observed simultaneously. This observation and an endothermic peak in the DSC curve show that two forms are correlated by a first‐order phase transition.
Raman and optical rotatory dispersion study of amylose in water–ethanol mixtures
Authors: Maciejewska Wanda , Kaczmarski Marceli 
Published: May 2005

AbstractRaman spectroscopy and optical rotatory dispersion techniques were used to investigate the transitions of the coil–helix and helix–helix forms and the conformation of functional groups in amylose in water–ethanol mixtures. The conditions of the transitions of a random coil form to the left‐ and right‐handed helix of V‐amylose under the influence of ethanol were determined. The Raman measurements also provided information on different trans and gauche conformations of CH2OH groups. The correlation between the process of adopting the right‐handed helix of V‐amylose and the (g, g) conformation of CH2OH groups is discussed.
Raman spectra of thin solid films. VII–Uranyl superphtalocyanine
Authors: Clavijo R. E. , Aroca R. , Kovacs G. J. , Jennings C. A. , Duff J. , Loutfy R. O. 
Published: May 2005

AbstractRaman and infrared spectra of evaporated uranyl superphthalocyanine (UO2SPc) films are reported. Raman spectra of UO2SPc (formed by five isoindoline subunits) depart from the general spectral trends observed in metallated phthalocyanines (four isoindoline subunits), and are indicative of very low molecular symmetry. Surface enhanced Raman scattering (SERS) spectra obtained on silver island films show appreciable differences from the normal unenhanced Raman spectra. This is unlike the situation for normal metallated phthalocyanines (where the SERS is simply the enhanced version of the normal Raman spectrum) and indicates a different interaction mechanism between the UO2SPc molecule and the metal islands.
Vibrational characterization of aluminum–oxo phthalocyanine films. IR, Raman and surface‐enhanced Raman spectroscopic studies
Authors: Zeng Z. Q. , Aroca R. , Hor A. M. , Loutfy R. O. 
Published: May 2005

AbstractThe vibrational characterization of bis(phthalocyanatoaluminum) oxide [(PcAl)2O] was attempted using infrared, Raman, SERS, RRS and SERRS spectra of thin solid films. Vibrational fundamentals observed for microcrystallites of (PcAl)2O dispersed in KBr, evaporated thin films and at submonolayer coverage of a SERS active surface were identified with characteristic vibrational frequencies of the phthalocyanine (Pc) moiety. Evidence for a certain degree of molecular organization in the evaporated thin solid films is presented, based on IR and Raman data.
Raman difference spectroscopy in measurements of molecules and molecular groups inside proteins
Authors: Yue Kwok To , Deng Hua , Callender Robert 
Published: May 2005

AbstractIn order to obtain the Raman spectra of small molecules inside proteins (or other large macromolecules) and/or small molecular groups of a protein, techniques were developed to perform sensitive Raman difference spectroscopy. The macromolecule–small molecule complex Raman spectrum is taken in addition to the Raman spectrum of the macromolecule, and the two are computer subtracted. For studies on proteins, it is necessary to use optical multichannel detectors, as spectrometers employing photomultiplier detectors are too slow optically to collect signals from dilute samples. The apparatus is described and characterized in detail. A subtraction fidelity of 0.1% can be achieved for samples, such as proteins, which contain broad bands in their Raman spectra. Hence it is possible to obtain fairly good Raman spectra of very small molecular groups inside proteins. An example from recent work is presented.
Resonance Raman investigation of the interaction of benzoquinone with amino acids
Authors: Santos P. S. , Gonçalves N. S. 
Published: May 2005

AbstractThe interaction of p‐benzoquinone with proline, pyrrolidine, trytophan and glutathione was investigated by resenance Raman spectroscopy. The intensely coloured solutions formed show an absorption maximum around 530 nm and the excitation of the Raman spectra in resonance conditions indicated in all cases an enhancement of several benzoquinone modes. Such behaviour strongly suggests the formation of an n–π* charge‐transfer complex, as suggested previously by other workers. The ESR spectra of the coloured solutions preclude the benzoquinone anion radical as the main chromophoric species in solution.
Raman spectrum of the [SnI3]− ion and other halogenostannate(II) complexes including mixed halides
Authors: Taylor Michael J. 
Published: May 2005

AbstractThe complete Raman spectrum of the pyramidal triiodostannate(II) ion [SnI3]− (ν1 = 162 cm−, strong, polarized; ν2 = 61 cm−, medium, polarized; ν3 = 148 cm−, strong, depolarized; ν4 = 48 cm−, strong, depolarized) is observed in a diethyl ether extract from a solution of tin(II) iodide containing hydriodic acid. Previous reports of the frequencies of [SnCl3]− are confirmed but for [SnBr3]− ν1 is revised from 211 to 205 cm−1. The complex acids H[SnX2Y] and H[SnXYZ] (X, Y or Z = Cl, Br or I) are observed in solvent extracts of tin(II) mixed halide solutions and a set of ν(Sn—halogen) frequencies is compiled. Appreciable co‐extraction of [SnX2(H2O)] occurs at halogen acid concentrations below 3 mol l−1.
Vibrational spectra and normal coordinate analysis of crystalline 3‐(4‐chlorophenyl)‐2‐cyanopropenonitrile
Authors: Bugueno‐Hoffmann R. , Meinnel J. 
Published: May 2005

AbstractThe polarized Raman and infrared spectra of crystalline 3‐(4‐chlorophenyl)‐2‐cyanopropenonitrile between 3150 and 3190 cm−1 are reported. The assignments of the different modes are discussed. To check the vibrational assignment, normal coordinate analysis was carried out. The force field consists of 110 force constants, 63 of which were transferred from benzene, chlorobenzene and tetracyanoethylene. Good agreement between most observed and calculated values was found, although there were some discrepancies between calculated and observed frequencies.
Surface‐enhanced Raman scattering of the redox pair CO(sep)3+/Co(sep)2+ on silver and copper electrodes
Authors: Bertolino J. R. , Temperini M. L. A. , Sala O. 
Published: May 2005

AbstractThe surface‐enhanced Raman spectra of the redox pair Co(sep)3+/Co(sep)2+ (sep: sepulchrate) adsorbed on silver and copper electrodes have been obtained in the skeletal region for these compounds and the results were consistent with the redox potential of the species. The role of the anions and cations of the support electrolytes in the adsorption of the Co(sep)3+ on a silver electrode suggests that the compound is adsorbed on the electrode via ion pair formation with the anion specifically adsorbed. From the behaviour of the Raman intensity of the CH2 symmetrical stretching vibration it was possible to estimate the pKa of the Co(sep)2+.
SERS of langmuir–blodgett monolayers: N‐octyl‐3,4:9, 10‐perylenetetracarboxylic monoanhydride and monoimide
Authors: Guhathakurta‐Ghosh U. , Aroca R. , Loutfy R. O. , Nagao Y. 
Published: May 2005

AbstractThe vibrational spectra of n‐octyl‐3,4:9, 10‐perylenetetracarboxylic monoanhydride (Oc‐PTCDO) and of n‐octyl‐3,4:9,10‐perylenetetracarboxylic monoimide (Oc‐PTCDNH) have been studied. Langmuir‐Blodgett (LB) films of both dye pigments were prepared and transferred to glass slides and silver surfaces for spectroscopic characterization. Using mixed LB monolayers of Oc‐PTCDNH and arachidic acid, the surface‐enhanced fluorescence of the monomer and aggregates was distinguished.
Stokes and anti‐stokes Raman scattering and electronic emission studies on dysprosium‐doped YBa2Cu3O7–δ
Authors: Bist H. D. , Gurjar R. , Upadhyay P. , Khulbe P. K. , Rao C. V. N. , Agarwal S. K. , Narlikar A. V. , Little T. S. , Durig J. R. 
Published: May 2005

AbstractLaser‐excited emission from YBa2Cu3O7–δ with 7.5% dysprosium nominally subsituted in place of yttrium is presented in the range 13 000–23 000 cm−1. In addition to the reported Raman lines in the CuO stretching region, a number of other spectral features were observed. These include a discrete luminescence with lines at 14 400 and 14 425 cm−1 and a broad emission with its peak position and band width varying with excitation wavelength. Additionally, an anti‐Stokes scattering, which has no apparent counterpart in the Stokes region, was observed. These observations may be of significance in the elucidation of the mechanism of high‐temperature superconductivity.