Intermolecular Vibrational Coupling Research Articles

Pressure Dependence of Resonant Intermolecular Vibrational Coupling etc.in Isotropic Raman Scattering of the v2 Mode of CH3I

AbstractThe pressure dependence of the isotopic dilution effect on the Raman band of the v2 mode of CH3I and CD3I has been investigated. In this way the resonant intermolecular vibrational coupling term has been separated from the other vibrational relaxation terms. It could be shown that the density dependence of this term is stronger then it is predicted from recent theories. The possible reasons for the discrepancy are discussed. The pressure dependence of a dynamical parameter τΩ is also obtained from the vibrational relaxation functions.

Computer Simulation of Liquid Methyl Iodide

AbstractA simple intermolecular potential — with five Lennard‐Jones‐centers and five point charges at the atoms of the molecule — has been used for a molecular dynamic simulation of liquid CH3I at 298 K and 213 K. Structural and dynamical data like radial distribution functions, reorientational correlation times and diffusion coefficients have been calculated and are in good agreement with experimental data. The distributions of some angular functions have been studied to obtain the most probable pair configuration. Particular the Wertheim D(12)‐function has been compared with results of Raman studies of intermolecular vibrational coupling.

Intermolecular vibrational coupling in dl-α alanine and its N-deutero isotopomer

The method of mixed isotopic crystal Raman spectroscopy shows no evidence for intermolecular vibrational coupling in dl-α alanine; the same method reveals coupling on the N-deutero analogue.

Vibrational spectroscopic investigation of metal cluster prototypes in the solid state: [M 3(CO) 12], where M = Os, Ru; metal-ligand stretching and MCO deformation region

A detailed analysis of the ν MC and δ MCO modes of [Os 3(CO) 12] and [Ru 3(CO) 12] has provided, for the first time, evidence for the presence of significant intermolecular vibrational coupling in this frequency region.

Intermolecular vibrational coupling in glycine

A study of isotopomers of α-glycine by Raman, inelastic neutron scattering and i.r. methods reveals intermolecular vibrational coupling on modes which, superficially, appear vibrationally insulated.

Intermolecular vibrational coupling associated with the 2ν2 features of the Raman spectrum of strontium nitrate

A comparative study of the Raman spectra of chemical and physically mixed crystals of Sr(14NO3)2 and Sr(15NO3)2 shows that the doubled features observed in the 1630 cm−1 (2ν2) region result from intermolecular vibrational coupling and not from multiple site occupancy.

A study of the structure of polymyxin B-dipalmitoylphosphatidylglycerol complexes by vibrational spectroscopy

The effect of the antibiotic polymyxin B on dipalmitoylphosphatidylglycerol (DPPG) bilayers has been studied by Raman and infrared spectroscopies and small-angle X-ray diffraction. Each polymyxin B molecule binds five DPPG molecules at physiological pH and induces a macroscopic phase separation of the complex rather than a lateral phase separation. Below the phase transition of DPPG/polymyxin B bilayers, the results obtained show that the intermolecular vibrational coupling is high and suggest that the acyl chains of the bound lipid are interdigitated and that the hydrophobic tail of the antibiotic does not penetrate this tight assembly. On the other hand, the phase transition of DPPG is shifted down from 41° C to 37° C in the complexes and remains highly cooperative. Above the phase transition of the complexes, the conformation of the acyl chains of DPPG is slightly more disordered as a result of the penetration of the polymyxin chain, but the structure of the glycerol backbone of the lipid does not seem to be affected. However, the rotational rate of the lipid appears to be restricted by the peptide.

Vibrational resonant coupling of liquid benzene

Abstract The intermolecular vibrational resonant coupling of liquid benzene has been examined by measuring shifts of the vibrational frequencies and changes in the line widths by isotopic dilution for the infrared-active ν 4 , ν 13 , and ν 14 , and the Raman-active ν 2 modes. The resonant coupling for the infrared-active modes is well explained by the transition-dipole-transition-dipole interaction, while the high-frequency shift of the ring breathing ν 2 mode suggests the presence of the charge transfer interaction. From the analysis of the frequency shift of the out-of plane ν 4 mode, it is suggested that the configuration of near neighbors in liquid benzene is similar to that in crystalline benzene.

Intermolecular interaction fluctuations, vibrational coupling and spectral band shapes for liquid water

An analysis of the band shapes for liquid water in the framework of the H-bond fluctuation concept has revealed two temperature-independent functions able of describing IR- and Raman spectra for HOD from −200 to +300°C and also some water thermodynamic characteristics. Account taken of vibrational coupling explains the H 2O and D 2O spectra including the temperature dependence of their profiles.

Transition dipole-dipole coupling between the antisymmetric stretching mode of azido ligands in K3

The nature and magnitude of intermolecular forces that couple the strongly polar ${\mathrm{N}}_{3}$ antisymmetric stretching vibration of the [Co(CN${)}_{5}$${\mathrm{N}}_{3}$${]}^{3\mathrm{\ensuremath{-}}}$ ions in ${\mathrm{K}}_{3}$[CO(CN${)}_{5}$${\mathrm{N}}_{3}$]\ensuremath{\cdot}2H $_{2}$O have been studied on the basis of previously reported results dealing with the crystal-structure determination and infrared and Raman spectra of this compound. The observed difference of 25 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ between the measured wave numbers for the frequencies of the ir- and Raman-active optical fundamental vibrations associated with the ${\mathrm{N}}_{3}$ antisymmetric stretching mode can be interpreted in terms of a linear-chain model of [Co(CN${)}_{5}$${\mathrm{N}}_{3}$${]}^{3\mathrm{\ensuremath{-}}}$ oscillators coupled through their ${\mathrm{N}}_{3}$ ligands via harmonic transition dipole-dipole forces operating between nearest neighbors on a chain. With this model, we obtain \ensuremath{\Vert}(\ensuremath{\partial}\ensuremath{\mu}/\ensuremath{\partial}${Q}_{3}$${)}_{0}$\ensuremath{\Vert}=263 esu/${\mathrm{g}}^{1/2}$ for the dipole-moment derivative of the ${\mathrm{N}}_{3}$ antisymmetric stretch, a value which can be compared with the corresponding value derived from integrated ir-absorption intensity measurements of ${\mathrm{N}}_{3}$${\mathrm{}}^{\mathrm{\ensuremath{-}}}$ ions isolated in alkali-halide lattices. A value ${f}_{3}$=+0.071 mdyn/\AA{} is calculated for the force constant of the interaction that couples such ${\mathrm{N}}_{3}$ vibrations of neighbor azide ions in ${\mathrm{K}}_{3}$[Co(CN${)}_{5}$${\mathrm{N}}_{3}$]\ensuremath{\cdot}2H $_{2}$O. The potentiality of combined ir and Raman spectroscopic techniques for the study of intermolecular vibrational coupling in solids is here emphasized.

Spectroscopic evidence of vibrational dipole–dipole coupling between nitrosyl groups in some nitroprussides

The nature and magnitude of the intermolecular vibrational coupling between nitrosyl groups in Sr[Fe(CN)5NO]⋅4H2O and Ba[Fe(CN)5NO]⋅2H2O have been studied quantitatively by IR spectroscopy. The isotopic dilution technique has been used by incorporating in the first compound up to 40% of 18O as N18O ligand in the crystal. The results can be interpreted by postulating a dynamic electric dipole–dipole interaction which operates between the polar NO stretching vibrations. The main features of the fine structure displayed by the NO stretching band in the infrared spectra of polycrystalline Sr[Fe(CN)5N(16O/18O)]⋅4H2O, and in single crystals of Ba[Fe(CN)5NO]⋅2H2O can be explained in terms of a linear-chain model of nitrosyls vibrationally coupled through transition dipole–dipole forces, with interactions between nearest neighbors. The value ‖(∂m/∂S)0‖=13 D/Å calculated on the basis of this model for the NO dipole-moment derivative agrees satisfactorily with the value reported from integrated IR absorption intensity measurements. The coupling force constants between neighboring nitrosyls f1=+0.172 mdyn/Å obtained for barium nitroprusside, and the average f̄1=+0.189 mdyn/Å value obtained for the strontium salt, show that these interactions are the strongest thus far reported for ionic solids.

ChemInform Abstract: POLARIZED INFRARED SPECTRA OF ORIENTED POLYCRYSTALLINE FILMS. INTERMOLECULAR VIBRATIONAL COUPLING IN CRYSTALLINE 2,4,6‐TRIBROMOANILINE

Chemischer InformationsdienstVolume 14, Issue 38 Physical Organic Chemistry ChemInform Abstract: POLARIZED INFRARED SPECTRA OF ORIENTED POLYCRYSTALLINE FILMS. INTERMOLECULAR VIBRATIONAL COUPLING IN CRYSTALLINE 2,4,6-TRIBROMOANILINE R. M. P. JAISWAL, R. M. P. JAISWALSearch for more papers by this authorJ. E. KATON, J. E. KATONSearch for more papers by this authorG. N. R. TRIPATHI, G. N. R. TRIPATHISearch for more papers by this author R. M. P. JAISWAL, R. M. P. JAISWALSearch for more papers by this authorJ. E. KATON, J. E. KATONSearch for more papers by this authorG. N. R. TRIPATHI, G. N. R. TRIPATHISearch for more papers by this author First published: September 20, 1983 https://doi.org/10.1002/chin.198338043AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume14, Issue38September 20, 1983 RelatedInformation

Polarized infrared spectra of oriented polycrystalline films. Intermolecular vibrational coupling in crystalline 2,4,6-tribromoaniline

Highly oriented crystal films of 2, 4, 6-tribromoaniline have been grown on cesium iodide substrates and their polarized infrared spectra recorded. In addition, the infrared and Raman spectra of this compound have been measured on bulk solid and solution samples. The factor group splittings arising from the intermolecular vibrational couplings in the crystal have been resolved and assigned and the crystal spectra correlated with the ‘‘isolated molecule’’ spectra according to their various symmetries. The interplane angle of the NH2 and phenyl groups is estimated as about 46° in the crystal. An earlier vibrational assignment has been modified to be consistent with the new experimental data obtained.

Intermolecular vibrational coupling in silver carbonate, Ag 2CO 3

In silver carbonate, Ag 2CO 3, an intermolecular vibrational coupling of the out-of-plane vibration of the carbonate ion is found similar to that in carbonates with the aragonite structure. The relative coupling in Ag 2CO 3, K r = 0.21, is weaker than in BaCO 3, K r = 0.28, which shows the smallest relative coupling of all investigated carbonates with aragonite structure. The spectra of 13CO 3 substituted Ag 2CO 3 can be understood quantitatively by use of our cyclic chain model.

Solid state studies.XIV. Mixed crystal and 13CO isotopic studies on intermolecular vibrational coupling in the ν (CO) region of M2(CO)10, M=Mn,Re

The ν (CO) Raman spectra of crystalline M2(CO)10 (M=Mn,Re) are interpretable on a molecular basis. Data from mixed Mn/Re crystal and statistical and nonstatistical 13CO-doped crystals of Mn2(CO)10 are used to establish that intermolecular vibrational coupling occurs in these crystals, showing that such a molecular description is not appropriate.

Solid state studies. Pt. XV. The v(CO) vibrational spectra of four crystalline η5-C5H5Fe(CO)2 species

Abstract The v(CO) infrared and Raman spectra of a series of related η3-C5H5Fe(CO)2X ( X = Sn or Ge species) compounds are reported. Relative band intensities give evidence of intensity stealing by an intermolecular vibrational coupling mechanism.

Solid state studies. Pt. XVI. The μ(CO) vibrational spectra of η5-C5H5Fe(CO)2M(C6H2)3, M = Sn, Ge

Abstract Pure and mixed crystal studies and intensity calculations have been carried out on the μ(CO) features of η 3 -C 5 H 5 Fe(CO) 2 M(C 6 H 5 ) 3 , M = Sn, Ge. This work demonstrates the presence of intermolecular vibrational coupling and supports the proposal that the vibrational unit cell of the tin compound is one half of the crystallographic.

A new theory of olfaction based on dispersion-induced optical activity.

OPTICAL activity is physically induced in achiral solutes dissolved in chiral solvents and is measurable as dispersion-induced circular dichroism (DICD)1–3. An intermolecular vibrational coupling mechanism of the induction2 has been analysed theoretically4 and is here proposed as the primary physical process in olfaction. This new theory of olfaction extends the well-known qualitative vibrational theory5–7, to encompass both chiral8,9 and achiral odorous substances10,11. A quantitative aspect of the new theory is supported by a strong correlation of the solvent-induced rotatory power of achiral ketones with their effectiveness as alarm pheromones for the ant species Iridomyrmex pruinosus11.

The Raman spectra of solid xenon tetrafluoride and its adduct with xenon difluoride

AbstractThe Raman spectra of the solids XeF4 and XeF2·XeF4 show effects arising in intermolecular vibrational coupling. Assignments based on factor group analysis are proposed, and the influence of intermolecular forces on the spectra of these and related compounds is discussed.

Midinfrared spectra of the plastic crystal phases of t -butyl bromide-h9 and -d9

The midinfrared spectra of the two plastic phases of t -butyl bromide are identical to each other and are very similar to that of the liquid, except for small decreases in the half-widths of the bands as the temperature is lowered. It is shown that molecular reorientation and intermolecular vibrational coupling contribute to the half-widths, and the residual width is attributed to site effects.