bluuebunny/crossref_metadata_2025 huggingface dataset:
Electronic and vibrational resonance Raman effect of OsBr62− in aqueous solution
Authors: Funato Yoshio , Kamisuki Toshio , Ikeda Ken‐Ichi , Maeda Shiro
Published: May 2005

Resonance Raman spectra of OsBr ion in aqueous solution were obtained using Ar+ laser exciting lines. Besides the ν1, ν2, and 2ν1 vibrational lines two extremely broad bands were observed at 2740 cm−1 and 4800∼4900 cm−1. The former was definitely assigned to the lowest spin‐orbit level T1g because of its inverse polarization, and the latter depolarized band was attributable to the next lowest T2g and Eg pair, confirming the absorption and luminescence results by Nims et al. Marked resonance enhancement was observed for the electronic and ν1‐vibrational lines in the first absorption region, while only ν1 was enhanced towards the second absorption.
A Raman spectroscopic study of the effect of hydrocarbon chain length and chain unsaturation on lecithin‐cholesterol interaction
Authors: Faiman Rosalind , Larsson Kåre , Long D. A.
Published: May 2005

The effect of cholesterol in equimolar concentrations on five different types of phospholipids in aqueous systems is reported. The phospholipids varied in chain length and chain unsaturation. This investigation confirms that the CH stretching region at 2700–3100 cm−1 is sensitive to conformational changes in the hydrocarbon chains. Moreover, this region of the Raman spectrum shows that small changes in band intensities can be correlated with the effect of the cholesterol on aqueous lecithin system both above and below the chain transition temperature (Tc). The results indicate that cholesterol moderates the change in chain mobility in both directions of the transition liquid crystal⇌gel phase. This effect is larger in lecithins with saturated chains compared to unsaturated chains.
High resolution Raman spectroscopy of gases with laser sources. X. The pure rotational spectrum of borazine
Authors: Kainnady Jakob V. , Weber Alfons
Published: May 2005

The pure rotational Raman spectrum of borazine (B3N3H6) vapor was photographed with a high resolution plane grating spectrograph. Two sets of rotational spectra, each consisting of R‐ and S‐branches, are observed and are assigned to the molecules 11B3N3H6 and 11B210BN3H6 which are concurrently present in a sample containing boron in its natural isotopic abundance. Spectral features which are due to the other two isotopic variants of borazine (11B10B2N3H6 and 10B3N3H6) were not detected. From the observed rotational lines the following constants were determined. For the symmetric top molecule 11B3N3H6, B = 0.175581 cm−1, DJ = 2.36 × 10−8 cm−1 while for the slightly asymmetric top molecule 11B2BN3H6B =1/2(A + B) = 0.177565 cm−1 and Dj = 4.39 × 10−8 cm −1. Since an appreciable number of molecules are in excited vibrational states at room temperature the observed spectra are composites of pure rotational transitions in these excited vibrational states as well as the ground state. The above constants are therefore averages over the ground and excited vibrational states of these molecules. Since resolved spectral features due to 11B10B2N3H6 and 10B3N3H6 were not detected the above constants must also be viewed as averages over these isotopic variants.

The B‐value for 11B3N3H6 was calculated using the electron diffraction structures for two suggested models, having C2 and D3h symmetry. These computed B‐values are in disagreement with the observed, spectroscopic B‐value by approximately 1.2%.
The vibrational spectra of mercury (I) bromate, sulphate, and nitrate dihydrate
Authors: Adams David M. , Barlow John , Tan Kang Hai , Taylor Michael J.
Published: May 2005

A low‐temperature single‐crystal Raman study of mercury(I) nitrate dihydrate is reported, together with low‐temperature powder Raman and i.r. spectra of the nitrate and of mercury(I) bromate and sulphate. The spectra are given consistent interpretations in terms of factor group analysis. Of note is assignment of ν(HgO) in the 250–265 cm−1 interval for coordinated bromate and sulphate; the demonstration that there is no correlation coupling for ν(HgHg) which consequently appears in the Raman spectra as a single band; and a mercurous ion rotatory mode region ca. 40 cm−1.
Infrared and Raman spectra of CuSO4, 5H2O; CuSO4, 5D2O; and CuSeO4, 5H2O
Authors: Berger J.
Published: May 2005

The Raman spectra of oriented single crystals of Copper (II) sulphate and selenate at 290 K and 150 K are reported and compared. Assignments are proposed for numerous internal modes of the crystals. Raman scattering tensors are calculated for the normal modes of (SO4)2− and (SeO4)2− and compared with experimental results. The structure and the part played by ligands (SO4)2− and (SeO4)2− in these crystals are stated precisely. The molecular complexes Cu(H2O)4 and Cu(D2O)4 are characterized by the assignment of their vibrational frequencies.
Excitation profile study of the resonance Raman effect of Ni (II)‐porphin
Authors: Kamisuki Toshio , Maeda Shiro , Kobayashi Hiroshi
Published: May 2005

Resonance Raman excitation profiles have been obtained for several non‐totally symmetric fundamentals (A2g and B2g or B2g of D4h symmetry) of Ni(II)‐porphin and some of their overtones in the region of the β absorption band using Ar and Kr ion laser exciting lines. Simulation calculations have been carried out for the observed profiles on the basis of Albrecht's formulation, and thereby vibronic coupling constants between the B and Q states have been evaluated.
Raman scattering of light by magnon‐spin flip excitations in antiferromagnetic semiconductors
Authors: Stasch A.
Published: May 2005

Estimates are given for the process by which the s – d exchange interaction may contribute to the Raman scattering due to the magnon–spin flip of the conduction electron processes in antiferromagnetic semiconductors. It is shown that for the typical values of the s – d exchange interaction integral, i.e. 0.01–0.1 eV, the extinction coefficient can be larger by two orders of magnitude than that in ferromagnetic semiconductors. The value of the extinction coefficient in antiferromagnetic semiconductors is found to be 10−9–10−11 cm−1 sr−1. It is also shown that the change of the value of an absorbed energy in an external magnetic field allows us to determine the gyromagnetic factor for the conduction electrons.
Study by Raman spectroscopy of order‐disorder phenomena occurring in some binary oxides with fluorite‐related structures
Authors: Michel D. , y Jorba M. Perez , Collongues R.
Published: May 2005

Order‐disorder phenomena in binary oxides with fluorite‐related structures were studied by Raman spectroscopy.

Raman spectra of disordered phases show broad bands, defects leading to selection rule breakdown. For well‐ordered structures, the scattering active modes observed are those allowed by crystal symmetry. Broadening of Raman peaks occurs when order defects are present: antiphase boundaries, distribution of different cations on equivalent crystallographic positions.
Polymorphism in cyclohexanol: A Raman spectroscopic study
Authors: James David W. , Shurvell H. F. , Parry Robyn M.
Published: May 2005

Raman spectra of the liquid and three solid phases of cyclohexanol are reported. Disorder in Phase 1 is shown to arise from random mixing of axial and equatorial conformers with free molecule rotation being unimportant. Axial to equatorial transformation is also shown to be unlikely in the solid phase. The equatorial isomer is shown to dominate the structures of phases II and III with phase III showing, in addition, intermolecular hydrogen bonding. The dominant mechanism for dielectric loss in the plastic phase is hydroxyl group rotation with molecule libration playing a minor rôle.
The pulsed laser and gated detection in Raman spectroscopy – a survey of the spectra of common substances including studies of adsorbed benzene
Authors: Yaney Perry Pappas
Published: May 2005

A pulsed‐laser Raman spectroscopy system using a doubled Nd: YAG laser is described. Comparisons between spectra recorded using the repetitive mode (low peak power and high duty cycle) with those recorded using the burst mode (high peak power and low duty cycle) are presented showing the degree of discrimination against fluorescence and stray ambient light obtained with a gated detection system. Spectra of nylon, acrylic, benzene with acridine orange, doped SrF2 crystal, and various forms of aluminum oxide and hydroxide are presented. The spectra suggest that the burst mode consistently gives, in all cases, at least a slightly improved Raman‐signal‐to‐noise ratio with some cases showing specular improvement. The results of a preliminary analysis of the Raman spectra of benzene liquid and vapor adsorbed on aluminum oxide/hydroxide powder using the gated burst mode are also presented. Although these spectra were found to differ from that of the liquid, some tentative line identities are offered.
The Raman spectra of (14NO)2 and (15NO)2 solids at 20 K
Authors: Durig J. R. , Griffin M. G.
Published: May 2005

The Raman spectra of (24NO)2 and (15NO)2 have been studied at 20 K. The far infrared of (14NO)2 at 20 K was also measured. The data were assigned on the basis of a C2ν molecular model. Normal coordinate calculations were performed for a variety of assignments. The assignment that yielded the best fit is presented. The solid state effects are discussed.
Resonance enhancement of local modes in the Raman spectra of mixed molecular crystals and biological polymers
Authors: Chen F. P. , Hanson D. M.
Published: May 2005

The effect of electronic resonances on the cross sections for Raman scattering from localized and delocalized vibrational modes is considered for the cases where the resonance is with a localized electronic state and with a delocalized electronic state. It is concluded that resonance with a localized electronic state increases the Raman cross section of the localized mode significantly more than that of the delocalized mode while resonance with a delocalized electronic state has the opposite effect. Furthermore, a coupling of electronic states following a conformational change in a polymer is predicted to decrease the resonance Raman cross section of a localized vibrational mode. Consequently, observations of such effects will serve to identify local phonon modes in mixed molecular crystals and provide information about conformational change in biomolecules.
Raman studies of platinum‐nucleoside complexes
Authors: Theophanides T. , Hadjiliadis N. , Berjot M. , Manfait M. , Bernard L.
Published: May 2005

The laser Raman spectra of a new series of platinum‐nucleoside complexes have been studied in solution at physiological pH values and in the solid state as powders. A qualitative analysis of certain vibrational modes responsible for various spectral lines is given. The carbonyl stretching frequency of guanosine and inosine is only slightly perturbed in the solid state whereas it is not affected at all upon coordination of the metal in water solutions. It is suggested that the binding of the free bases takes place at the Pt‐N7 site in all these complexes.
Weaker spectral features in the Raman spectra of MN3 (M = K, Rb, Cs)
Authors: Ti S. S. , Kettle S. F. A. , Ra Ø.
Published: May 2005

The weaker spectral features in the Raman spectra of MN3 (M = K, Rb, Cs) in the region 1240–1360 cm−1 are reported. The present study indicates that the two‐phonon modes involving ν2 can be analysed solely in terms of k = 0 selection rules whilst the two‐ and three‐phonon bands involving internal and external combination modes require a critical point analysis. There are several possible assignments of a multiphonon band of the latter type; its appearance apparently depends on proximity to an intense fundamental mode, from which it presumably steals intensity.
Spectre Raman et Transition de Phase dans le La2 (SO4)3, 9H2O
Authors: Abenoza Michel , Vinh Luu Dang , Rull‐Perez Fernando , Pastor José Maria
Published: May 2005

Polarized Raman spectra of single crystals of La2 (SO4)3, 9H2O and La2 (SO4)3, 9D2 O have been recorded at room temperature and assignments to the zero wave vector modes proposed. Analysis of the spectra shows the non‐individuality of ions and molecules involved in these crystals and the existence of hydrogen bonds of various lengths. The systemiatc temperature study of Raman spectra shows a singularity in the variation of band intensities in the 273–283 K region which confirms the existence of a phase transition at this temperature.
Interference between resonance and preresonance Raman scattering
Authors: Zgierski M. Z.
Published: May 2005

The theory of interference effects between preresonance scattering from an intense electronic transition and resonance scattering from a forbidden electronic transition is formulated. A simple closed formula for the cross‐section of a totaliy‐symmetrical fundamental line is derived for the case where the vibrational structure of both electronic transitions is smeared out. This formula reproduces very well recently obtained experimental excitation profiles in such complex compiunds as tris (ethylenediamine) cobalt (III) chloride and tetrabromopalladate ion.
Spectres Raman de Résonance de la Diéthylcyanine
Authors: Mejean T. , Forel M. T.
Published: May 2005

The resonance Raman spectra of aqueous solutions of the diettylcyanine ion are recorded from 100–4000 cm−1 using all the exciting lines of an Ar+ laser and the 6328 Å line of a HeNe laser. Experimental results, intensities and depolarization ratios, are discussed using Albrecht's theory. The calculated and experimental intensity laws obtained for some normal modes are analysed. An assignment of all the Raman bands is proposed, based upon comparison with infrared spectra and the results of a normal modes calculation.
The resonance Raman spectrum of ClO2. An example of the introduction of morse potentials in the Raman tensor
Authors: Bourgeois M. T. , Jacon M. , Van Labeke D. , Eysel H. H.
Published: May 2005

In this paper, the resonance Raman spectrum of ClO2 in solution, which cannot be quantitatively interpreted within the usual approximations, is described using a Morse function for the nuclear potentials in the lower and upper states. The absorptionspectrum and the Raman excitation profiles are calculated and compared with the experimental results. The study of the depolarization ratio show, a result which cannot be obtained by consideration of the relative intensities.
Absolute Raman intensities of CHCl3 and CDCl3 and force field for chloroform
Authors: Bermejo D. , Escribano R. , Orza J. M.
Published: May 2005

The absolute Raman intensities of the fundamental bands of vapour HCCl3Jand DCCl3 have been measured with an experimental accuracy of ten per cent. The vibrational potential function for chloroform has been calculated by a standard least squares forceconstant refinement including data on anharmonicity corrected values of the 12C/13C displacements and also the absolute intensities measured in this work. The results are compared with those of Previous works and the influence of the intensity data upon the refinement is discussed.
Etude par Spectrométrie Raman de la Transition de Phase Structurale des Tétrachloro et Tétrabromo‐1,2,4,5 Benzenes
Authors: Pasquier B. , Le Calvé N.
Published: May 2005

Raman and infrared spectra of crystalline1,2,3,4,5‐tetrachloro‐ and tetrabromobenzenes have been analysed between 10 and 100 cm−1 over a range of temperature from 10 K to 400 K. An assignment of lattice modes is given. The first‐order phase transition is of a displacive type as shown by the behaviour of librational modes. The small value of the estimated β critical exponent in the νT/ν0 = (Tc − T/Tc)β experession is interperted in terms of predominant short‐range interactions in these molecular crystals.
Raman spectra of single crystal s‐trithiane and s‐trioxane. Lattice vibrations
Authors: Thomas Dwaine M.
Published: May 2005

This paper reports the assignments for the lattice vibrations of single crystal s‐trithiane and s‐trioxane, using the Raman scattering technique. For s‐trithiane, spectral measurements were made at 300 K and 30 K; nine bands were observed and assigned. For s‐trioxane, three bands were observed and assigned from 300 K results.
Experimental study of the properties of ZrO2Y2O3 and HfO2Y2O3 solid solutions
Authors: Chistyi I. L. , Fabelinskii I. L. , Kitaeva V. F. , Osiko V. V. , Pisarevskii Y. U. V. , Sil'Vestrova I. M. , Sobolev N. N.
Published: May 2005

The Mandel'shtam‐Brillouin spectra of single crystals of ZrO2–Y2O3 and HfO2Y2O3 solid solutions have been measured and the results explained qualitatively. Using the methods of Mandel'shtam‐Brillouin spectra and ultrasound propagation the elastic and photoelastic constants of single crystals of ZrO2Y2O3 and HfO2Y2O3 solid solutions have been found and their dependence on the composition obtained. The elastic and photoelastic properties of single crystals of these solid solutions are discussed.
Raman and infrared study of the low temperature phase of solid H2S and D2S
Authors: Anderson A. , Binbrek O. S. , Tang H. C.
Published: May 2005

Raman, infrared and far infrared spectra of polycrystalline samples of H2S and D2S at 80 K and 18 K have been recorded. Many new features have been detected, including some very low frequency Raman modes. The assignments of these and other peaks are discussed in terms of the known crystal structure and compared with previous results. The spectra are in general compatible with the low symmetry and unusually large unit cell of this molecular crystal. The principal features are described qualitatively in terms of interactions involving the four hydrogen bonds linking each molecule in the two dimeasional network.
Solvent — solute interactions in solutions of mercury(II) halides and halogeno‐complexes in aprotic donor solvents
Authors: Waters D. N. , Kantarci Z.
Published: May 2005

Raman spectral data for the species HgX2, HgX3− and HgX42− (X = Cl and Br) in solution in 24 class A donor solvents are presented. The complex ions were present in the solutions as lithium salts. The frequencies (ν1) of the symmetric stretching vibrations of HgX2 and Hg3− correlate well with solvent donicity (DN) and with other measures of solvent donor strength. A two‐parameter regression equation of the form ν1 = ao + a1(DN) + a2(Eτ), where Eτ is the Dimroth‐Reichardt electrophilicity parameter, gives good correlations for the HgX42− ions. Evidence based on (i) the frequency values of the symmetric and antisymmetric (ν3) stretching vibrations of HgCl2 and HgBr2, (ii) the Raman intensities of the ν3 mode of HgBr2 and (iii) the depolarization ratios of the ν1 bands of HgCls and HgBr2 in various solvents, supports the view that these molecules in solution undergo a progressive departure from linearity as a result of increasing solvent coordination to the mercury atom. For solvents of high donor strength (e.g. pyridine), the XHgX interbond angle may approach 120°.
Application of laser Raman multichannel spectroscopy to a kinetic study in the liquid phase
Authors: Crunelle‐Cras M. , Merlin J. C.
Published: May 2005

A multichannel spectrometer with photoelectric image devices, interfaced with a data acquisition and handling system, permits temporal analysis of Raman spectra. This system enables rapid kinetic studies to be made. The fast oxidation of sulphite ion by bromate ion in an acid medium (0.46 N) is given as an example. The rate of disappearance of the bromate ion has been determined and shows an important hydrogen ion dependence.
Lattice vibrations of crystalline p‐chloroaniline
Authors: Righini R. , Califano S.
Published: May 2005

Infrared and Raman spectra of p‐chloroaniline are reported and assigned for the low‐frequency lattice region at 300 K and 78 K. The observed frequencies of the lattice modes are compared with those calculated using a semi‐empirical intermolecular potential. The agreement is very good, so confirming the high degree of transferability of the atom‐atom potentials. The equilibrium conditions are also well fulfilled by the potential. The total calculated crystal energy is −13.5 kcal mol−1.
Higher‐order Raman spectra of GaP
Authors: Sushchinsky M. M. , Gorelik V. S. , Maximov O. P.
Published: May 2005

The second‐, third‐ and fourth‐order Raman spectra of GaP monocrystals have been investigated, and the relative intensities measured. It is found that the fourth‐order Raman maxima are only a little less intense (about 5 times) than the third‐order ones. Polariton scattering from GaP has also been investigated. It is found that the intensities of polariton scattering and second‐order scattering are similar.
Raman spectra of halate ions as solid solutions in sodium chlorate and bromate lattices
Authors: Fornari B. , Mattei G. , Mattioli L. , Pagannone M.
Published: May 2005

The fundamental vibrational modes of the halate ions as solid solutions in NaClO3 and NaBrO3 lattices have been studied by laser Raman spectroscopy, both at room and at low (80 K) temperature. The four predicted modes have all been observed and assigned for each halate ion. The local symmetry of the doping ions in the host lattices at both temperatures is discussed.
A cassegrain collector with unusually high light grasp
Authors: Hester R. E.
Published: May 2005

The design and performance characteristics of a Cassegrain mirror system suitable for Raman spectroscopy are described. This system has a number of outstanding advantages over more conventional lens systems, including its unusually high speed and achromaticity.
Raman spectrum of gaseous perchloryl fluoride and the deconvolution of bands due to a single isotopic species
Authors: Murphy W. F. , Sunder S. , Katz H.
Published: May 2005

The vapor phase Raman spectrum of perchloryl fluoride has been observed under higher resolution and sensitivity conditions than reported previously, and a temperature study has been carried out for the bands due to the totally symmetric modes. A method has been developed to extract the band due to a single isotopic species from the observed spectrum of a mixture of two isotopic species and applied to the present case. The remaining hot band structure is discussed.
The low frequency spectra of π–σ complexes
Authors: Bobrov A. V. , Kimel'fel'd Ja. M. , Mostovaya L. M. , Mostovoy A. B.
Published: May 2005

The low frequency (30–200 cm−1) Raman spectra of Cl2 and Br2 complexes with ethylene, cyclohexene and benzene have been investigated at 77 K. Vibrations of two types are observed in this region of the spectra for olefin–X2 complexes: valence and probably torsion vibrations.
The temperature dependence of the Raman spectrum of ammonium perrhenate
Authors: Korppi‐Tommola J. , Devarajan V. , Brown R. J. C. , Shurvell H. F.
Published: May 2005

Raman spectra of NH4ReO4 and ND4ReO4 have been recorded at several temperatures between 77 K and 353 K. As the temperature is increased, several bands due to both internal and external modes of the perrhenate ion are shifted to lower wavenumbers and there is a discontinuity in the slope of the wavenumber versus temperature curves near 200 K. This behaviour is correlated with recent NQR and X‐ray diffraction results and supports the suggestion of a higher order phase transition near 200 K. The bands due to the ammonium ion vibrations are broadened as the temperature is increased and the librational lattice mode is no longer observable above about 200 K. The nature of the motion of the ammonium ion in the lattice is discussed and it is pointed out that the presence of a librational lattice mode does not necessarily indicate an absence of reorientational motion.
Raman and far infrared spectra and conformation of 1,2‐diiodotetrafluoroethane
Authors: Powell David L. , Gustavsen J. E. , Klaeboe P. , Nielsen C. J.
Published: May 2005

Raman spectra of 1,2‐diiodotetrafluoroethane in the liquid and solid states as well as far infrared spectra of the vapour and of a benzene solution have been obtained. These data complement earlier infrared spectra. The compound is shown to exist in the trans conformation in the crystal and as a mixture of trans and gauche conformers in the other phases. Vibrational assignments are made, aided by normal coordinate calculations.
Raman intensities in single crystals of NaPF6·H2O
Authors: Heyns A. M.
Published: May 2005

The Raman spectra of single crystals of NaPF6·H2O are reported. By transferring the Raman tensors for the Oh point group to the NaPF6·H2O crystal, the relative intensities of the PF modes are calculated and a good agreement is obtained between the calculated and observed values. The Raman tensors for the internal modes of the water molecules in NaPF6·H2O are obtained and it is shown why the totally symmetric bending mode of these molecules is not observed in the Raman effect. The ratio of ∂α/∂S1 values for the PF and H2O groups in this study corresponds to the one calculated from a delta potential function.
Association Moléculaire et Paire Ionique dans le Verre et le Liquide du ‘Monohydrate de l'Acide Nitrique’
Authors: Herzog‐Cance M. H. , Potier J. , Potier A. , Dhamelincourt P. , Sombret B. , Wallart F.
Published: May 2005

The Raman spectra of the equimolecular mixture HNO3·H2O in the liquid and glassy states have been investigated in the range 4000–50 cm−1. At least four species have been characterized: (i) The free molecular association H2O…HONO2 νOH(H2O) = 3550 cm−1 (3440 cm−1) and νOH(HNO3) = 2930 cm−1 (2915 cm−1) respectively in the liquid (and the glass). (ii) The free ionic pair (H2OH)+…(ONO2)− that give a splitting (Δν = 170 cm−1) of the ν3(NO) vibration. (iii) Free HNO3 molecules: νNOH = 940 and 950 cm−1 respectively in the liquid and the glass. (iv) The ‘nitric acid trihydrate’: H7ONOνOH between 3100 and 3300 cm−1.
A Raman spectroscopic study of aqueous and methanolic tetramethylammonium chloride solutions
Authors: Kabisch† G. , Klose M.
Published: May 2005

Previous vibrational assignments for Me4N+ are examined and in some respects revised. Frequency and intensity changes in the Raman spectra of Me4NCl solutions with variations of concentration and solvent (D2O and CD3OH) were observed mainly in the CH stretching and NC4 bending regions. These are interpreted in terms of cation‐anion associations the extent of which is found to be much larger in methanolic than in aqueous solution. The effects of temperature on the Raman bands proved to be much smaller than those of concentration or solvent changes.
Ramanspektroskopische Untersuchungen von Zirkoniumtetrachlorid
Authors: Brockner W. , Demiray A. F.
Published: May 2005

Raman spectra of crystalline, molten and gaseous ZrCl4 have been measured. The Raman frequencies of the solid have been assigned on the basis of the recently determined crystal structure. In molten ZrCl4 polymeric units with similar structural elements as in the solid and also ZrCl4 molecules will be formed. ZrCl4 molecules are present in the gaseous state.
Etude par Effet Raman des Librations de l'eau dans La2 (SO4)3. 9H2O
Authors: Rull F. , Pastor J. M. , de Saja J. A. , Luu Dang V.
Published: May 2005

Polarized Raman spectra of single crystals of La2(SO4)3. 9H2O and La2(SO4)3. 9D2O were recorded from 400 to 800 cm−1. In this region the observed modes were assigned and the librations of water molecules were identified. Potential barrier values were calculated using the V = ½ V0 (1 –cos nφ) potential for the torsional oscillations. Calculations were in complete agreement with the dissociation energy value for the OH…︁O hydrogen bond, evaluated at 25–29 KJ/mol. The frequency shifts and the polarization of the Raman lines of isotopic species allow the correlation of the spectra.
Raman spectra of solid perylene–TCNQ complexes
Authors: Bandrauk A. D. , Truong K. D. , Salares V. R. , Bernstein H. J.
Published: May 2005

Resonance and pre‐resonance Raman spectra are presented for the 1:1 and 3:1 solid complexes of perylene with tetracyanoquinodimethane (TCNQ). Selective resonance enhancement was observed for perylene. A study of the frequency dependence of the Raman intensities shows that, although these are weak complexes, complexing has a marked influence on the scattering intensities.
Polarized resonance Raman spectra of an oriented diphenylpolyene
Authors: Margulies L. , Stockburger M.
Published: May 2005

Measurements of polarized Raman intensities of partially oriented molecules were shown to be useful for obtaining information about the components of the scattering tensor and the degree of orientation in anisotropic samples. The polarized resonance Raman (RR) spectra of all‐trans‐1,14‐diphenyltetradecaheptaene (DPTH) incorporated in a stretched polyethylene film were studied. The DPTH molecules are highly oriented in the polymer matrix with their longitudinal axis in the direction of stretching. The different components of the scattering tensor for the totally symmetric vibrations of DPTH were determined in the case of resonance excitation. It was found that the diagonal element αzz (z is defined along the polyene chain) gives the largest contribution to the RR intensity. However, the two off‐diagonal elements αzy and αyz also contribute significantly and have different magnitudes. The physical origin of these off‐diagonal elements and of the asymmetry of the scattering tensor are discussed in terms of the vibronic coupling theory.
High resolution Raman spectroscopy of gases with laser sources. XIV—The pure rotational spectra of dimethylacetylene and dimethyldiacetylene
Authors: Thomas P. M. , Weber A.
Published: May 2005

The pure rotational Raman spectra of dimethylacetylene (DMA), dimethylacetylene‐d6 (DMA‐d6) and dimethyldiacetylene (DMDA) vapor excited by the λ0 = 4579 Å,4765 Å,4880 Åand 5145 Å lines of a single mode argon ion laser have been photographed under high resolution. The spectra were recorded on Kodak IIIa‐J spectroscopic plates hypersensitized by baking in nitrogen. The spectra of DMA and DMA‐d6 are those of symmetric top rotors showing the R‐ and S‐branches, whereas in the spectrum of DMDA only the S‐branch is observed. The spectra of DMA and DMA‐d6 were analyzed by including an Hj (J + 3/2)5 term in the frequency formula for the S‐branch, while for DMDA the conventional expression was employed. The results for the molecular constants are, in cm−1,magnified image These constants are average over the ground and excited vibrational states. The quoted errors are five standard deviations. The rCC and rCC bond lengths in dimethylancetylene are related by the expression magnified image.
Raman scattering of hydrogen chemisorbed on silica‐supported nickel
Authors: Krasser W. , Renouprez A. J.
Published: May 2005

The chemisorption of hydrogen on silica‐supported nickel has been investigated by Raman spectroscopy at low temperatures. In the spectral range of 200–2500 cm−1, three systems of vibrational bands are detected. The vibrational bands in the high frequency range at 1999 cm−1 and 2030 cm−1 are interpreted as ṽ(NiH) stretching vibrations of a linear chemisorbed species. At 950 cm−1 a weak broad vibrational band is observed, which is assigned to a multibonded surface species. Two vibrational modes in the spectral range of 600–800 cm−1 result from δ(NiH) deformation vibrations of chemisorbed hydrogen. The spectral data are compared with the vibrational spectrum of chemisorbed deuterium.
The Raman spectrum of the 2200 cm−1 wavenumber region of gaseous ethylene‐d4
Authors: Hegelund Flemming
Published: May 2005

The Raman spectrum of the ν1 and ν5 fundamental bands of ethylene‐d4 has been analysed to yield a number of upper state rotation vibrational constants.magnified image The c‐type Coriolis resonance between the two fundamental bands is discussed.
The totally symmetric rotation‐vibrational Raman bands of benzene
Authors: Jensen Hans Birger , Brodersen Svend
Published: May 2005

The ν1 and ν2 Raman bands of gaseous C6H6 were photographed with a resolution of 0.20–0.25 cm−1. The J structure was resolved, but not the K structure. The analysis yielded several constants, primarily B0 = 0.189751 ± 0.000025 cm−1 (standard error). This number differs significantly from the value obtained by Cabana et al. from the rotational structure of the ν11 infrared band.
The Raman spectra of some hexa‐aquo metal(II) hexafluorosilicate(IV) (M(H)2O)6SiF6) salts between 10 K and 300 K
Authors: Lewis John , Jenkins Tudor E.
Published: May 2005

Raman spectra of Ni(H2O)6SiF6, Ni((D2O)6SiF6 and Fe(H2O)6SiF6 have been observed between room temperatures and 10 K, and the measured lines assigned to the various modes of vibration. The spectra of the nickel salts are consistent with R3 symmetry at all temperatures, but below ∼ 230 K the lattice band spectra of the ferrous salt cannot be fitted to R3m or R3, which is consistent with the recent findings that there is a phase transition at about 250 K with the low temperature space group being P21/c. The weakness of the water vibrational bands at room temperature is interpreted in terms of the barrier to 180° flip motion of the water molecules and the coupling of 180° flipping with the water vibrations. The Raman spectrum of polycrystalline Mg(H2O)6SiF6 at 300 K is also given for comparison.
A difference in polarizability between normal and sickle cell oxyhemoglobin as revealed by resonance Raman spectroscopy
Authors: Barrett T. W.
Published: May 2005

This report describes differences in the polarization of the resonance Raman lines at 1317, 1142 and 1012 cm−1 with respect to an exciting wavelength (5730 Å), which is within the long wavelength absorption region, for human normal hemoglobin AA versus sickle cell hemoglobin AS. The evidence indicates that the NCa band region differs in the two hemoglobins. These differences may be related to the differences in dipole moment between normal and sickle cell hemoglobin originally reported by Pauling.1 The usefulness of the resonance Raman technique in providing additional microscopic information in a study of abnormal hemoglobins is discussed.
Raman spectra of halogen‐substituted methanes in the liquid state: Depolarization ratios of the totally symmetric vibration bands
Authors: Fukushi Kohji , Kimura Masao
Published: May 2005

Polarized Raman measurements have been made for the totally symmetric vibration bands of a series of halogen‐substituted methanes in the liquid state at room temperature. The effect of polarization mixing due to divergence was examined experimentally and eliminated. The observed systematic variations in depolarization ratio are discussed in connection with the bond polarizability theory.
Spectres de Vibration des Acides Cyclobutane‐1,1 Dicarboxyliques et de Leurs Sels de Potassium en Solution Aqueuse
Authors: Fabrègue Eliane , Cassanas Geneviève , Bardet Lucette
Published: May 2005

The Raman and infrared spectra of 1,1‐cyclobutane dicarboxylic acids 1,1‐CB(COOH)2, 1,1‐CB(COOD)2 and of its potassium salts 1,1‐CB(COO)2 HK, 1,1‐CB(COO)2DK et 1,1‐CB(COOK)2 in aqueous solution have been investigated in the range 3500–200 cm−1. An assignment of the fundamental vibrations is proposed. The analysis of the polarization ratio of the Raman lines has enabled us to conclude that these compounds belong to point group Cs, the cyclobutane ring being puckered.
Resonance Raman spectra of a single crystal linear chain platinum compound, [Pt(en)2][Pt(en)2Cl2](ClO4)4
Authors: Papavassiliou G. C. , Theophanides T. , Rapsomanikis R.
Published: May 2005

Strong resonance enhancement of the Pt(IV)Cl stretching vibration of a single crystal of [Pt(II)‐(en)2][Pt(IV)(en)2Cl2](ClO4)4 has been observed with the incident light vector parallel to the linear chain Pt(IV)Cl ⃛Pt(II)(Z). This resonance enhancement is much reduced in the E ⟂ Z spectrum where a normal Raman spectrum is also observed. In agreement with these results the visible reflection spectrum with E‖Z shows a maximum at 435 nm, which is absent with E ⟂ Z.
Aromatic bromination catalysis on zeolites. II—Raman spectroscopic analysis of the reaction of activated Br2 with benzene
Authors: Tsai Peter , Cooney Ralph P.
Published: May 2005

Raman spectral evidence indicates that benzene, when reacted with the zeolite adsorption complex MX + Br2, forms a surface donor‐acceptor complex with the adsorbed Br2 on sites III and sites II. At lower Br2 coverage (with sites II occupied and sites III unoccupied) the benzene reacts instantaneously to form addition products.
The pure rotational and vibration‐rotational Raman spectra of 1H3H and 2H3H
Authors: Edwards H. G. M. , Long D. A. , Mansour H. R. , Najm K. A. B.
Published: May 2005

The pure rotational and vibration‐rotational Raman spectra of the hydrogen species 1H3H and 2H3H have been recorded and analysed. The following rotational constants, vibration‐rotational constants and bond lengths were obtained:magnified image The re values are compared with those of 1H2, 1H2H, 2H2 and 3H2 and a weighted mean re value for the hydrogen molecule was calculated.
Raman optical activity: Spectral simulation of the conformer dependent CCl stretching vibrations in 1‐chloro‐2‐methylbutane
Authors: Prasad P. L. , Nafie Laurence A. , Burow Duane F.
Published: May 2005

The atom dipole interaction model for Raman optical activity is utilized to evaluate certain chirality parameters for 1‐chloro‐2‐methylbutane. The necessary normal coordinates and the associated vibrational frequencies for the CCl stretching motion of all nine conformers of this molecule are evaluated. The Raman optical activity spectrum as well as the ordinary Raman spectrum pertaining to CCl stretching vibrations are simulated and compared with the corresponding experimental spectra. Favorable agreement between the calculated and experimental results is obtained except for the overall strength of the ROA spectra where the calculated results are more than an order of magnitude smaller.
Vibrational spectra and normal coordinate analysis of difluorophosphine‐d0 and ‐d1
Authors: During J. R. , Zozulin A. J. , Odom J. D. , Streusand B. J.
Published: May 2005

The Raman and infrared spectra of difluorophosphine and difluorophosphine‐d1 in the gaseous and solid phases from 100 to 3000 cm−1 have been recorded. The six fundamental frequencies have been assigned on the basis of group frequencies, depolarization ratios, band types and isotopic shifts. A normal coordinate analysis was carried out. Very little mixing was found to occur between the normal modes. Thermodynamic functions were calculated from the observed frequencies and previously reported moments of inertia.
A Raman spectroscopic study of methyl ammonium chloride. II—the hydrogen stretching vibrations
Authors: Meinander N. , Bergström G. , Forss S. , Stenman F.
Published: May 2005

The Raman spectra of the three crystalline modifications of eight isotopic species of methyl ammonium chloride and their isotopic solid solutions have been recorded in the temperature range 70–300 K. The CH3 and NH bands in the hydrogen stretching region of the spectra have been identified and an assignment of the CH3 bands is proposed. The large number of methyl bands in the CH stretching region is explained as the result of strong coupling of the symmetric hydrogen stretching fundamental and overtones of the CH3 bending fundamentals. Correlation and crystal field splittings of the bands are also discussed.
Raman spectroscopic studies of the dipalmitoylphosphatidylcholine/glucagon and the dipalmitoylphosphatidylcholine/cardiolipin/insulin systems
Authors: Mendelsohn Richard , Taraschi Theodore , Van Holten Robert W.
Published: May 2005

The phospholipid hydrocarbon chain conformation has been measured in lipid/protein complexes of dipalmitoylphosphatidylcholine (DPPC)/glucagon and dipalmitoylphosphatidylcholine/cardiolipin/insulin using the conformation‐sensitive CH stretching region of the Raman spectrum as a probe. In the DPPC/glucagon complex, which models hydrophobic interactions between (membrane) proteins and phospholipids, the Raman data show that the lateral interactions between phospholipid hydrocarbon chains have been greatly disrupted in the complex. The primary effect of the protein appears to be to induce a disordering of the phospholipid. The gel–liquid crystal phase transition of DPPC is reduced in temperature and is rendered less cooperative. In the DPPC/cardiolipin/insulin complex, which models the electrostatic interaction between peripheral membrane proteins and phospholipids, the primary effect of complexation is to rigidify and order the hydrocarbon chains of the phospholipids. The main interaction of the protein occurs with the cardiolipin and results in the neutralization of the excess charge. The ternary complex undergoes a broad phase separation not present in the binary phospholipid mixture.
High frequency vibrational modes of poly(dA) · poly(dT) and poly(dAT) · poly(dAT)
Authors: Baret J. F. , Carbone G. P. , Sturm J.
Published: May 2005

The Raman and infrared spectra of poly(dA) · poly(dT) and poly(dAT) · poly(dAT) have been recorded. Normal coordinate analyses have been performed for these two polymers to obtain the fundamental modes. We use a valence force field deduced from literature values and from a refinement of a diethyl phosphate potential. Non‐bonded interactions are not included. Extensive descriptions of each mode are given allowing qualitative understanding of some of the spectral difference found between the two polymers.
The Raman and infrared spectra of the dicyanoiodate (I) ion
Authors: Chadwick B. M. , Long D. A. , Qureshi S. U.
Published: May 2005

The interaction of iodine cyanide and cyanide in aqueous solution has been reinvestigated and it has been confirmed that a complex cyanide ion, the dicyanoiodate(I) ion [I(CN)2]− is formed. This ion has been isolated in the solid state for the first time, as its tetraphenylarsonium, tetraphenylphosphonium and caesium salts. Infrared and Raman spectroscopic studies of these salts are reported. These spectra are fully consistent with a linear centrosymmetric (D∞h) structure for the [I(CN)2]−ion. Assignments are made for six of the seven fundamentals of the [I(CN)2]−ion in the caesium salt.
Etude Structurale du Tétrachloroaluminate de Sodium: Comparaison des Spectres de Diffusion Raman de la Famille des MAlCl4 (M = Li, Na, K, Rb, Cs, NO, NH4) à l'Etat Solide
Authors: Wallart F. , Lorriaux‐Rubbens A. , Mairesse G. , Barbier P. , Wignacourt J. P.
Published: May 2005

The crystal structure of NaAlCl4 (a = 10.322(3) Å, b = 9.886(3) Å, c = 6.167(2) Å, Z = 4, space group P212121) was refined to final R and Rω values of 0.025 and 0.039 respectively, for 1240 reflections with I>2σ(I). The thermal motion of the AlCl4− anion is in keeping with the TLS rigid‐body analysis. Crystal and polycrystalline samples of this compound were studied by Raman scattering and an assignment of the observed bands was proposed. The Raman spectrum was compared with those of all members of alkaline (Li, Na, K, Rb, Cs) and pseudo‐alkaline (NH, NO+) tetrachloroaluminates in the solid state.
Raman study of the thermal decomposition of dioxygenyl hexafluoroarsenate, O AsF
Authors: Griffiths J. E. , Distefano Doreen , Sunder W. A.
Published: May 2005

The apparent vapor transport of O2AsF6 by sublimation at modest temperatures is shown to proceed via the reversible reaction, OAsF⇄O2F˙ + AsF5, involving a free radical mechanism. This reaction path is in marked contrast to the vapor transport of O2PtF6, O2RuF6 and O2RhF6 species which proceed via dissociation and recombination with charge transfer, OPtF⇄O2 + PtF6.
Raman scattering of benzene and deuterated benzene chemisorbed on silica‐supported nickel
Authors: Krasser W. , Ervens H. , Fadini A. , Renouprez A. J.
Published: May 2005

The Raman spectrum of chemisorbed benzene and deuterated benzene has been measured in the frequency range of 200–3400 cm−1 in backscattering geometry. In order to suppress the strong second‐order light‐scattering spectrum of glass, a difference Raman scattering cell has been developed. The vibrtational bands are shifted only slightly compared with liquid benzene. Additional bands are found, which are symmetry forbidden in free benzene. These bands result from symmetry lowering produced by the site symmetry of the surface. Compared with the Raman spectrum of liquid benzene, the vibrational bands of chemisorbed benzene are strongly enhanced.
Raman spectroscopic study of glassy aqueous zinc halide solutions
Authors: Kanno H. , Hiraishi J.
Published: May 2005

Raman spectra of aqueous zinc halide solutions are obtained in both liquid and glassy states. It is shown that the detection and characterization of weak low frequency Raman bands in aqueous solutions is much easier in the Raman spectrum for the glassy state than for the liquid state. Comparison of the spectra shows that the tetrahedral ZnX ions are the most stable ionic entities in the glassy state.
Vibrational spectra and conformations of vinyloxirane
Authors: Kalasinsky V. F. , Pechsiri S.
Published: May 2005

The infrared spectra of gaseous and solid vinyloxirane have been recorded, while Raman spectra of all three physical states have been obtained. The vibrational data for the liquid and vapor phases are consistent with the presence of three conformations, the s‐trans and two nonequivalent gauche forms. The energy separations between the most stable s‐trans and each of the other confromers have been determined for the liquid state to be 1.1 ± 0.2 and 0.8 ± 0.2 kcal mol−1 by measuring the temperature dependence of sets of Raman lines. A complete vibrational assignment is proposed for the s‐trans conformer, and the identities of the less stable conformers are discussed in terms of previous studies of related molecules.
A Kinetic isotope effect in purinic 8‐CH exchange of guanine nucleotides: Measurement by Raman spectroscopy
Authors: Thomas G. J. , Lane M. J.
Published: May 2005

Rates of deuterium exchange of the 8‐CH groups of 5′‐rGMP and cGMP in D2O solutions (KH) are compared with rates of protium exchange of the 8‐CD groups of the same compounds in H2O solutions (KD). The ratio of the two rate constants (kH/kD) defines an isotope effect which is a combination of primary kinetic and solvent isotope effects, the former predominating. The net isotope effect was measured by Raman spectrophotometry over the temperature range 30–80°C. The Arrhenius activation energies (Ea) and pre‐exponential frequency factors (A) were also determined. The average values of kH/kD are 1.82 ± 0.15 for 5′‐rGMP and 1.43 ± 0.06 for cGMP. The relatively small kinetic isotope effects are indicative typically of an unsymmetrical transition state. The ratio E/E is unity in both compounds, indicating an early or reactant‐like transition state. The present data are consistent with, and extend the range of, the Bell–Goodall curve relating log (kH/kD) to ΔpK of the two acid–base systems involved in the proton transfer during the rate‐determining step.
Carbon–hydrogen stretching and bending vibrations in the Raman spectra of poly (methylmethacrylate)
Authors: Dirlikov Stoil , Koenig Jack L.
Published: May 2005

The Raman spectra of three deuferated poly(methylmethacrylate) derivatives, —(CH2C(CD3)COOCD3)n, —(CD2C(CH3)COOCD3)n and —(CD2C(CD3)COOCH3)n, are measured and the assignment of the CH stretching and bending vibrations of the methylene, α‐methyl and ester methyl groups of PMMA is made.