Showing papers in "Journal of Molecular Structure in 1980"

TL;DR: In this article, a modified overlapping sphere model was used for the electronic structure of methane, ethane, propane, isobutane and neopentane, which represented the only set of theoretically determined charges which can be related directly to experiment.

TL;DR: In this article, the structure of methyl silatrane was investigated by gas-phase electron diffraction at 185° C. The result obtained for the Si-N distance (2.45(5) A) indicates essentially no dative bonding between Si and N in the gas phase.

TL;DR: In this paper, the IR and Raman spectra of an anhydrous phase of calcium oxalate are discussed in relation to the effects of dehydration and compared with the monohydrate.

TL;DR: A spectroelectrochemical method based on the enormous intensity enhancement for Raman scattering on an electrode surface is used in order to obtain high resolution vibrational spectra of nucleic acid components in rather dilute aqueous solutions.

TL;DR: In this article, the ground states of ten 3- and 4-membered ring compounds have been optimized using the gradient method at the 4-21 level, and an optimized 3-3-21 basis has been constructed, and the importance of including d-functions is demonstrated.

TL;DR: The average ring C-C and C-H distances are nearly identical with those of benzene, but the ring exhibits marked asymmetry, including an unexpected coupling between the ring c-C distances and the angle of methyl rotation as discussed by the authors.

TL;DR: In this article, the IR spectra of twelve imidazole (Him) complexes and their deuterated analogues are discussed, and the internal modes of the NO 3 − and ClO 4 − ions are discussed in relation to the known or proposed structures of the complexes.

TL;DR: In this article, the Raman spectra of polycrystalline l-alanine analogs were obtained and a normal coordinate analysis was carried out based on the experimental frequencies of the four isotopic analogs and a 34 parameter valence-type force field defined in terms of local symmetry coordinates.

TL;DR: In this paper, the free energy difference between the two tautomeric forms of 4-oxo-6-methylpyrimidine in the vapour phase has been calculated.

TL;DR: Silicon-29 NMR spectra have been recorded for aqueous solutions of sodium silicate in the alkaline pH range using silica enriched in the 29 Si isotope as mentioned in this paper.

TL;DR: In this paper, the low temperature fluorescence behavior of p-N-pyrrolidino-benzonitrile (5) and p-n-piperidinitrile(6) is described and a model of diffusion limited internal rotation is able to account for this difference.

TL;DR: In this paper, a model with D 2h symmetry has been used for the determination of small deviations of the benzene ring from D 6h symmetry caused by the chlorine substituents, with an increase from 120° to 1216 ± 2° of the internal angle at the ipso carbon and a shortening of the distance between the two ipso atoms.

TL;DR: In this paper, the selfassociation of methanol and ethanol and the hetero-association with CH 3 OHβO(CH 3 ) 2 have been studied by means of matrix isolation technique.

TL;DR: In this paper, the 6 fundamentals observed can be assigned to the planar molecule OSiF 2, and the value of the force constant of the SiO double bond, which was calculated as approximately 9 × 10 2 N m −1 in earlier investigations, is confirmed.

TL;DR: In this article, the potential energy curves governing the vibration are deduced from the experimental data and are found to have a single broad minimum for both molecules, implying that the amido hydrogens are copianar with the N-C�O atoms, but that the resistance to their out of plane displacement is small.

TL;DR: In this article, the authors obtained the spectrum of 3 and 4-fluoronitrobenzene in several torsional states and of 2-and 2,4,6-trifluoronite in the ground state, and the inertial defects were used to show that the 3-and 4-substituted molecules are planar.

TL;DR: In this paper, the Naphthazarin I and its OD analogue, I-d 2, are analyzed in terms of a centrosymnetrical structure with highly mobile protons in intramolecular hydrogen bonds with double minimum potentials.

TL;DR: In this paper, a gas-phase electron diffraction at nozzle-tip tempera- tures of 18, 110 and 215°C was performed on a mixture of anti and gauche confor- mers with the anti form the more stable.

TL;DR: In this paper, the photoelectron spectra of uracil, lumazine, iso-alloxazine, its 10-methyl derivative and 1,5-dihydroiso-labeled alloxazines were analyzed with the aid of earlier spectra for pyrazine, quinoxaline, o -phenylenediamine.

TL;DR: In this paper, the results of an IR spectroscopie study are presented for six new dianiline metal tetracyanometalate complexes, M(an)2M'(CN)4 (M = Mn, Fe, Co or Cu and M'= Ni; M = Ni or Cd and M's = Pt; an = aniline).

TL;DR: In this article, the authors present the state-of-the-art of FTIR spectroscopy in the characterization of polymeric structure, which they call FTIR-VQA.

TL;DR: In this paper, the polarized IR and Raman spectra of single crystals of KDy(MoO4)2 are presented and discussed in relation to molecular and crystal structures, and the spectra indicate additional intermolecular interactions due to pair coupling of the molybdate tetrahedra.

TL;DR: In this paper, a detailed analysis of the factors which govern the energy and geometry of the four C 10 hydrogen bonds in the tripeptide molecule and in the two monomeric amides is presented.

TL;DR: In this paper, the fundamental vibrations of cyclic S n Se 8-n (n = 7-2) molecules have been calculated using a modified Urey-Bradley force field with 9-14 independent force constants whose values have been adapted from those of Se 8 and S 8.

TL;DR: In this paper, gas phase electron diffraction at nozzle-tip temperatures of 70°C and 77°C was used to study bromoacetyl chloride and bromomethane bromide.

TL;DR: A composite absorption band with a maximum below 100 cm −1 is observed for polar non-hydrogen bonding molecules in the pure liquid and in binary mixtures with CCl 4 as mentioned in this paper.

TL;DR: In this paper, data from spectroscopic studies of diatomic and polyatomic inert gas complexes, so-called van der Waals molecules, are presented from spectrograms.

TL;DR: Piperidine-, morpholine-4-, N-methylpiperazine-4, and thiornorpholine -4-carbodithioate complexes of chromium(III), manganese (III), tin(II), and lead(II) are prepared and characterized by chemical analyses, spectroscopic methods (I.R. and electronic spectra), magnetic susceptibilities, conductivity measurements and mass spectra.