bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laser‐Raman spectroscopy of biomolecules 16‐temperature dependence of the conformation of crystalline ribonuclease a from x‐ray diffraction and Raman spectroscopy
Authors: Gilbert William A. , Lord Richard C. , Petsko Gregory A. , Thamann Thomas J. 
Published: May 2005

AbstractX‐ray diffraction and Raman spectra have been studied for crystalline ribonuclease A as a function of temperature, up to 50°C for diffraction and 70°C for the spectra. Changes in the geometry of hydrogen‐bonded tyrosines, disulfide groups and methionine side chains have been followed by means of the x‐ray diffraction results, and the corresponding effects on the Raman spectra have been ascertained. The temperature trend of the Raman spectra of the crystalline enzyme corresponds surprisingly closely to that observed by Chen and Lord for the aqueous enzyme. It appears that intermolecular forces in the crystal are less important to the temperature stability of the enzyme than intramolecular forces. The close correspondence of the crystalline and aqueous temperature trends enables conformational changes in the crystal which affect the Raman spectrum to be identified with corresponding changes in aqueous conformation as shown by the aqueous Raman spectrum.
Measurement of weak depolarization ratios of the Rayleigh scattering of gases using Raman spectroscopy
Authors: Monan Max , Bribes Jean‐Luc , Gaufrès Robert 
Published: May 2005

AbstractUsing a spectroscopic method suggested by Murphy, the depolarization ratios for the Rayleigh scattering of several gases have been measured, lying in the range of 10−2 to 5*10−5. The values obtained are generally lower than those found by previous authors who used the classical method, especially in the case of extremely small depolarization ratios. For hydrogen and deuterium sulphides, which present the smallest depolarization ratios ever observed, a difference is found between the isotopomers although this at the limit of the experimental error.
Resonance Raman spectra of phenoxy and monosubstituted phenoxy radicals
Authors: Shindo Hitoshi , Hiraishi Jiro 
Published: May 2005

AbstractThe resonance Raman spectra of the phenoxy radical and its deuterated species have been observed. The characteristic features of the spectra have been interpreted on the basis of a large contribution from a quinonoid type resonance structure. The assignment of each band is discussed. The effects of ortho and para substitution on the Raman spectra are also discussed.
Linear solid state array detectors in Raman spectroscopy
Authors: Hug W. , Surbeck H. 
Published: May 2005

AbstractWe demonstrate the rapid recording of liquid phase anti‐Stokes vibrational and gas phase rotational spectra with an unintensified solid state detector. The ratio of the Stokes and anti‐Stokes intensities of the 522 cm−1 vibration of toluene (Wilson 6a) does not appear to agree with theoretical predictions, in contrast to nearby lines. This possibility of a direct comparison accentuates the advantage of the simultaneous multichannel recording without drift. We also discuss the signal‐to‐noise performance of unintensified detectors and point out the limits where intensification is preferable.
Raman and infrared studies on new anticancer inorganic ring systems. 2—Pentaziridinocyclodiphosphathiazene (NPAz2)2NSOAz, Az = (NC2H4)
Authors: Manfait Michel , Alix Alain J. P. , Lahana Roger , Labarre Jean‐François 
Published: May 2005

AbstractA Raman and infrared investigation of SOAz 2, one of the two allotropic varieties of a new anticancer agent, SOAz, has been made in order to have a better understanding of its interactions with DNA. A third allotropic variety, named SOAz 3, was found to be produced when heating SOAz 2. The SOAz 3 → SOAz 2 transformation is also described. SOAz 3 appears to be the conformation of SOAz in aqueous solution and consequently seems to be the moiety which is responsible for its anticancer effectiveness.
Raman and infrared spectra, vibrational assignments and barriers to internal rotation of cis‐ and trans‐1‐chloropropene
Authors: Durig J. R. , Guirgis G. A. 
Published: May 2005

AbstractThe Raman spectra of both cis‐ and trans‐1‐chloropropene were obtained between 3500 and 20 cm−1 for the vapor, liquid and solid states and the polarization data were obtained for the fluid phases. The infrared spectra were recorded between 3500 and 50 cm−1 for both compounds in the vapor and solid states. Complete vibrational assignments based on depolarization data, infrared band contours and group frequencies are presented for both molecules on the basis of Cs symmetry. The methyl torsion for trans‐1‐chloropropene was observed in the infrared spectrum of the vapor as a series of transitions with the 1 ← 0 fundamental having a frequency of 208 cm−1; from this fundamental frequency a periodic barrier to internal rotation was calculated to be 844±16 cm−1 (2413±46 cal mol−1). Although the methyl torsion was not observed directly for cis‐1‐chloropropene, the first overtone was tentatively assigned in the Raman spectrum of the vapor at 205 cm−1. Many of the fundamentals for both the cis and trans molecule appear as doublets in the spectra of the solids which indicates that there are at least two molecules per primitive cell for each solid. These results are compared to corresponding quantities in some similar molecules.
Raman optical activity in carbonyl deformations
Authors: Barron L. D. , Torrance J. F. , Vrbancich J. 
Published: May 2005

AbstractThe contribution of carbonyl deformation co‐ordinates to normal modes is discussed in the context of the Raman optical activity of chiral molecules containing a carbonyl group attached to a cyclic system. A comparison of the Raman optical activity spectra of 3‐methylcyclohexanone and 3‐methyl methylenecyclohexane provides convincing evidence for the dominant role of carbonyl deformations in the generation of the large couplet at about 500 cm−1 in 3‐methyl cyclohexanone. The spectra of nopinone, β‐pinene and 5‐methylcyclohex‐2‐ene‐1‐one are also discussed. Finally, a model bond polarizability theory of Raman optical activity in carbonyl deformations is presented.
Fermi resonance in Raman and infrared spectra of Ni(CH3COO)2·4H2O and its deuterated analogue
Authors: Raghuvanshi G. S. , Pal Mahendra , Bist H. D. 
Published: May 2005

AbstractThe doublet at 962–906 cm−1 observed in the room temperature spectra of Ni(CH3COO)2. 4H2O is attributed to the ν4 state of the acetate group undergoing strong Fermi‐type anharmonic interaction with a two‐phonon hybrid state associated with a water libration exhibiting characteristic hypsochromic shift and hyperchromic effect with decreasing temperature. In the deuterated analogue another doublet at 706–666 cm−1 is associated with the v5 state of the acetate group and another two‐phonon hybrid state, also associated with a D2O libration, exhibiting hypsochromic shift but the hypochromic effect. The Fermi interaction enhances in the hydrate and diminishes in the deuterate as the temperature is lowered.
Structure in nitrate glasses: Multiple anion sites or random continuum?
Authors: Leong Wah Hing , James David W. , Carrick Malcolm T. 
Published: May 2005

AbstractThe Raman spectra have been studied of tertiary glasses formed by the progressive replacement of Ca(II) by Mg(II) in an equimolar Ca(NO3)2:KNO3 mixture. The Raman bands of the three internal modes of the nitrate ion show progressive growth of a new set of components as the Mg(II) concentration increases. The changes are interpreted in the light of previous experimental and theoretical studies. A case is made for the existence of discrete anion sites in which the field perturbing the anion is dominated by one species of cation. Even in the case of the (Ca/K)NO3 glass, there is evidence for discrete sites rather than a continuum of anion environments.
Vibrational spectra and assignments of ethylene‐diamine and its deuterated derivatives
Authors: Giorgini Maria Grazia , Pelletti Maria Rosaria , Paliani Giulio , Cataliotti Rosario Sergio 
Published: May 2005

AbstractThe infrared and Raman spectra of ethylenediamine and its deuterated derivatives have been studied in both the liquid and solid states. An assignment of the fundamental vibrational modes for the four molecules is proposed assuming for the liquids a gauche configuration (C2 symmetry); the assignment is based on depolarization values, isotopic shifts and classic group frequencies correlations.
Determination of A0 and Dk for CD3I from the ν4 Raman and IR bands
Authors: Poulsen Carsten , Brodersen Svend 
Published: May 2005

AbstractThe ν4 Raman band of CD3I has been recorded at a resolution of 0.28 cm−1. A weighted least‐squares analysis, including data from the ν4 infrared band recorded by Peterson and Edwards, gave A0 = 2.59608±0.00010 cm−1 and DK = (1.98±0.10)x10−5 cm−1 in addition to values for ν, (Aζ)4, ΔA and ΔB The ν4 state is essentially unperturbed. Using literature values for the αA constants, Ae was calculated as 2.6200±0.0008 cm−1, indicating a value of re = 1.03192±0.00015 Å for the distance of the deuterium atoms from the figure axis.
Time‐resolved resonance Raman study of transient benzooxazolinic merocyanines
Authors: Albert J. L. , Aubard J. , Dubois J. E. 
Published: May 2005

AbstractThe time‐resolved resonance Raman spectrum (excitation: 532 nm, 30 ns laser pulse; optical multichannel detection) of the short‐lived species generated by UV flash irradiation of a benzooxazolinic spiropyran in toluene or benzene, has been obtained. The CW resonance Raman spectrum of a related permanent benzooxazolinic merocyanine closely resembles the spectrum of the transient species. A tentative assignment of the Raman bands is proposed in order to characterize the bonds directly involved in the π‐electron delocalization of the merocyanines.
Temperature dependence of the low frequency Raman scattering spectra in tetramethylammonium tetrachlorozincate
Authors: Henocque J. , Sauvajol J. L. , Lefebvre J. , Marion G. 
Published: May 2005

AbstractThe behaviour of some lattice modes in the Raman spectra (wavenumber shift range 0–50 cm−1) has been investigated for (N(CD3)4)2 ZnCl4 and (N(CH3)4)2 ZnCl4 over the temperature range 183–523 K.
Vibrational spectroscopy at high pressures: 44—thallous carbonate
Authors: Adams D. M. , Hatton P. D. , Taylor I. D. 
Published: May 2005

AbstractRaman spectra of thallous carbonate have been studied to c. 52 kbar and mid‐IR spectra to 36 kbar. Details of the assignment have also been established using single‐crystal IR reflectance and Raman spectroscopy. Phase transitions were found near 13 and 38 kbar on the basis of the Raman evidence, thus supporting the earlier conclusions of Meisalo and Kalliomaki based on x‐ray powder and optical results. Analysis of possible space group relations between phases III (ambient) and IV showed that IV must be orthorhombic and adopt one of the D groups, where n = 17, 19, 21, 25 or 28. Structural relationships between the phases are discussed.
Soft mode in diamantane, C14H20
Authors: Jenkins T. E. 
Published: May 2005

AbstractDiamantane (C14H20) is a molecular solid which has a second order phase transition at 35K driven by a Raman‐active soft‐mode. There has been some controversy regarding the symmetry of soft‐mode and it is shown that this must be triply degenerate. Possible space groups of the low temperature phase are presented.
Temperature dependence of the Raman active B3g torsional mode of sulphamic acid
Authors: Ratcliffe C. I. , Sherman W. F. , Wilkinson G. R. 
Published: May 2005

AbstractThe Raman active B3g torsional mode of a single crystal of sulphamic acid has been observed as a function of temperature from liquid nitrogen to room temperature. The frequency decrease and markedly asymmetric broadening with increasing temperature have been characterized and are discussed.
Diode array versus photomultiplier for measuring the UV‐excited resonance Raman spectra of enzyme‐substrate transients
Authors: Carey P. R. , Sans Cartier L. R. 
Published: May 2005

AbstractThe construction of a multiplex system for recording the resonance Raman (RR) spectra of enzyme‐substrate complexes in the near‐UV region is described. The instrument is based on commercially available components consisting of a 2 W UV krypton ion laser, a triple spectrograph (in which the first two monochromators act as a zero dispersion, variable bandpass filter) and an intensified diode array. The performance of this system is compared with that of a double monochromator with a photomultiplier as a detector. The enzyme‐substrate systems chosen as examples for the comparison offer a difficult experimental challenge because they evolve rapidly and have poor optical homogeneity. In addition, a simple apparatus is described for recording the RR spectra of enzyme‐substrate complexes in cryosolvents at temperatures as low as −50 °C.
Correction of measured resonance intensity profiles using a monochromator‐photomultiplier response function
Authors: Chinsky Laurent , Peticolas Warner L. , Turpin Pierre‐Yves 
Published: May 2005

AbstractThe ultraviolet transmission response function of a double monochromator Raman spectrometer has been obtained in the 28 000–40 000 cm−1 range, using a very simple method, assuming that the two halves of the double monochromator are rigorously identical in the transmission of light. The measured transmission response function of a commercially available double monochromator has been found to vary sharply in the region of 33 000 cm−1. Such a substantial variation in transmission must be taken into account when Raman intensities are measured as a function of the excitation wavelength, even when an internal standard is used, as the absolute frequency of the Raman standard is different from the absolute frequencies of the Raman lines of the sample. This is particularly the case when overtone and combination band intensities are measured relative to a fundamental of the internal standard, since the overtone frequencies are often displaced by more than 1000 wavenumbers from the fundamentals. Failure to make such corrections can lead to substantial errors in a measured resonant Raman excitation profile.
Spectroscopic and electrochemical studies of transition metal tetrasulfonated phthalocyanines: 2—resonant raman spectra of aqueous solutions of cobalt and iron tetrasulfonated phthalocyanines
Authors: Simic‐Glavaski B. , Zecevic S. , Yeager E. B. 
Published: May 2005

AbstractRaman spectra of the polarized and depolarized light scattered from cobalt and iron tetrasulfonated phthalocyanines in aqueous media at various pH values are discussed and correlated with previously obtained data. The Raman vibrational modes from pyrrole and benzene were used for a tentative band assignment in the frequency range from 200 to 1700 cm−1.
Low‐frequency depolarized light scattering from aqueous solutions of halogen acids and their sodium salts
Authors: James David W. , Irmer Raimund 
Published: May 2005

AbstractThe depolarized light scattering from 3 to 300 cm−1 has been studied for aqueous solutions of the halogen acids over a wide range of concentrations. The scattering profiles are interpreted on the basis of a four band component model in which two of the bands are centred on the exciting line and there are two shifted frequencies of ∼60 and ∼180 cm−1. The width of the bands is found not to give a measure of the cooperative rotational relaxation but is related to the decrease in dynamic coupling of oscillators in the network because of the presence of foreign ions. The intensity variations are dominated by polarizability fluctuations from both polarizable anions and the hydrated proton. The influence of the proton is similar to that of the iodide ion. There is also evidence for a reinforcement of local order at low electrolyte concentration.
Spectroscopic analysis of the 1:1 tetracyanoquinodimethane‐9,9′‐bifluorenylidene charge‐transfer complex: Infrared, UV‐visible and resonance Raman spectra
Authors: Angeloni L. , Sbrana G. 
Published: May 2005

AbstractThe 1:1 TCNQ‐9,9′‐bifluorenylidene π‐complex (TCNQ=tetracyanoquinodimethane) was investigated by infrared, UV‐visible and Raman spectroscopy. Resonance Raman spectra of the solid were measured and from the analysis of the excitation profiles the lower energy electronic levels of TCNQ and 9,9′‐bifluorenylidene in the complex were identified. A blue shift of the low‐lying electronie levels of the interacting molecules was observed. The mechanisms responsible for the Raman intensity of TCNQ in the complex and in solution are discussed.
Spectroscopic studies of explosives: 1—detection of nitro compounds on silica gel and carbon by non‐resonant Raman spectroscopy
Authors: Carver F. W. S. , Sinclair T. J. 
Published: May 2005

AbstractRaman spectra have been obtained from trace amounts of propanetriol trinitrate, tetramethoxymethane tetranitrate, 1,3,5‐trinitro‐1,3,5‐triazacyclohexane and 2,4,6‐trinitro‐1‐methylbenzene adsorbed on silica gel and on activated charcoal. Detection limits for these nitro compounds lay between 1 and 10 μg on silica gel and between 20 and 40 ng on activated charcoal.
Analyse Vibrationnelle et Structurale en Série Aliphatique Saturée: 5—Spectres de Vibration de l'Acide Ethylmalonique et de ses Sels Alcalins en Solution Aqueuse
Authors: Delarbre J. L. , Maury L. , Bardet L. 
Published: May 2005

AbstractLes spectres Raman et infrarouge de l'acide éthylmalonique [C2H5CH(COOH)2, C2H5CD(COOD)2] et de ses sels alcalins [C2H5CH(COOH)(COOK), C2H5CD(COOD)(COOK) et C2H5CH(COOK)2, C2H5CD(COOK)2] en solution aqueuse ont été enregistrés de 3500 à 200 cm−1. L'analyse du facteur de dépolarisation nous a permis de conclure que l'acide et le dianion appartiennent au groupe de symétrie Cs le sel acide appartenant au groupe C1. Une attribution des vibrations fondamentales est proposée.
Raman spectra of CdSb
Authors: Houde D. , Jandl S. , Carlone C. , Arushanov E. 
Published: May 2005

AbstractRaman spectra of CdSb at 100 K are presented. Twenty‐two out of the twenty‐four predicted phonons are detected. Frequencies of different modes are low, implying motions associated with large reduced masses. Their values are comparable to those obtained from infrared measurements.
Resonance Raman spectra and excitation profiles of some rifamycins
Authors: Angeloni L. , Marzocchi M. P. , Smulevich G. 
Published: May 2005

AbstractThe resonance Raman Spectra of rifamycin SV, its sodium salt and rifampicin have been investigated under various physical conditions. The excitation profiles of the strongest Raman bands have been measured using an Ar+ laser for excitation. The proposed vibrational assignment indicates that the magnified image group is the main portion of the chromophore for both rifamycin SV Na salt and rifampicin molecules. Excitation profile studies of the δ(CO−) and ν(COH) vibrations indicate the presence of a single electronic transition in the visible region. In addition these two modes derive their intensities from 0–1 vibronic transitions whereas no evidence for the contribution due to the 0–0 term is found. This is explained in terms of coupling with the other totally symmetric modes and broadening due to phonon‐electron interactions.
Raman scattering study of CsH2PO4
Authors: Aoki Magane , Kasahara Masaru , Tatsuzaki Itaru 
Published: May 2005

AbstractRaman spectra of CsH2PO4 have been observed at 295 and 83 K in the frequency shift region 40–1200 cm−1. According to factor group analysis, Raman active vibrational modes at k = 0 are classified as follows; 13Ag + 8Bg in the paraelectric phase and 23A + 22B except for acoustic modes in the ferroelectric phase. No soft modes were observed in the A class modes. The frequency and the line width of one of the internal modes of the HPO ions were measured as a function of temperature in the scattering geometries b(cc)a* and c(bb)a*, where a* is perpendicular to the bc plane. Remarkable anisotropy was found in the temperature dependence of both the frequency and the line width. The results are discussed by considering that the phase transition is of an order‐disorder type and the relaxation time of the polarization fluctuation is very long compared with the inverse of the associated phonon frequencies.
Anharmonic effects in Raman‐active modes of PbCl2
Authors: Melo F. E. A. , Filho J. Mendes , Moreira J. E. , Lemos V. , Cerdeira F. 
Published: May 2005

AbstractThe behaviour of representative lines in the room temperature Raman spectrum of PbCl2 under the influence of a high hydrostatic pressure (up to 80 kbar) is reported. Pressure derivatives and mode Grüneisen parameters are calculated for 13 of the 18 Raman‐active modes. Combining these results with previous data for the temperature dependence of these phono frequencies, the implicit (thermal expansion) and explicit (vibrational amplitude‐driven) contributions are separated from ωj(T). This separation shows that anharmonic effects are stronger for vibrations involving motion of chlorine ions than for those involving only lead atoms.
Molecular reorientation and vibrational relaxation in dibromomethane
Authors: Chen S. J. H. , Schwartz M. 
Published: May 2005

AbstractThe polarized and depolarized Raman spectra of the ν2 (CH2 bend) and ν3 (CBr stretch) vibrations in dibromomethane have been studied as a function of temperature throughout the liquid range. Reorientational correlation times derived from the two modes were simllar in both magnitude and dependence on temperature. This result, together with other structural data, suggests that the rotational dynamics of this molecule in the liquid phase are quasi symmetric‐top in character. Vibrational dephasing times calculated from the two lineshapes were also of the same magnitude. However, modulation times determined via the Kubo lineshpae formalism varied markedly between the vibrations. This provides evidence that vibrational dephasing of the bending and stretching modes are influenced by different intermolecular forces in the liquid.
Raman spectra of fully deuteriated syndiotactic and isotactic poly(methyl methacrylate)
Authors: Neppel Anton , Butler Ian S. 
Published: May 2005

AbstractThe Raman spectra of solid fully deuteriated syndiotactic (D8s‐PMMA, 55%) and undeuteriated isotactic (H8i‐PMMA, 92%) poly(methyl methacrylate) have been recorded in the 3500–200 cm−1 range at ambient temperature. Vibrational assignments are proposed for most of the observed bands and, in the case of D8s‐PMMA, the data have resolved some of the inconsistencies in the spectra of the undeuteriated polymer.
Micro‐Raman spectroscopy of chromosomes
Authors: de Mul F. F. M. , van Welie A. G. M. , Otto C. , Mud J. , Greve J. 
Published: May 2005

AbstractRaman spectra of intact chromosomes (Chinese hamster), recorded with a microspectrometer, are reported. The spectra could be assigned to protein and DNA contributions. Protein and DNA conformations and the ratio of base pairs in DNA were determined.
Inverse Raman spectroscopy of bilirubin and its ditauride
Authors: Hillig Kathy J. Dien , Morris Michael D. 
Published: May 2005

AbstractThe inverse Raman spectrum of bilirubin and bilirubin ditauride were measured under pre‐resonant conditions. Spectra in chloroform and dimethyl sulfoxide were assigned by comparison with model compounds and on the basis of the known effects of the solvents on the internal hydrogen bonding in bilirubin. The band assignments were used to interpret the spectra of bilirubin ditauride in aqueous solution. Evidence is presented for strong hydrogen bonding to the pyrrole NH bonds and to the lactam rings. It is proposed that hydrogen bonding to water is facilitated by photoactivation and, in turn, stabilizes photohiliruhin.
Experimental observation of the Raman spectrum of 1‐Methylsilatrane hydrochloride
Authors: Imbenotte M. , Palavit G. , Legrand P. 
Published: May 2005

AbstractThe Raman spectrum of 1‐methylsilatrane hydrochloride has been recorded. The disappearance of the 354 cm−1 band, found in the spectrum of 1‐methylsilatrane, is in agreement with the assignment of this vibration to the SiN stretching mode on the basis of a previous a priori normal coordinate treatment.