Détermination des constantes de force et des amplitudes moyennes de vibration du sous-sulfure de carbone, C3S2

1968 ◽  
Vol 46 (16) ◽  
pp. 2641-2643 ◽  
Author(s):  
Alpha O. Diallo
Keyword(s):  
Vibrational Frequencies ◽  
Force Constants ◽  
Mean Square ◽  
Mean Amplitudes Of Vibration ◽  
Symmetrical Structure ◽  
Symmetry Coordinates ◽  
Shrinkage Effect ◽  
The Mean ◽  
Generalized Mean

The theory of the generalized mean amplitudes of vibration has been applied to the C3S2 molecule, which possesses a linear symmetrical structure. The numerical values of the force constants and the mean square parallel and perpendicular amplitudes at 298°K of all bonded and non-bonded pairs of atoms are calculated from spectroscopic vibrational frequencies by the Cyvin and Morino–Hirota methods, utilizing the symmetry coordinates. The "shrinkage" effect constants are also evaluated by means of the perpendicular mean square amplitudes.

Normal coordinate analysis of diacetylene and dicyanoacetylene

1969 ◽  
Vol 22 (6) ◽  
pp. 1123 ◽  
Author(s):  
K Ramaswamy ◽  
K Spinivasan
Keyword(s):  
Potential Energy ◽  
Interaction Force ◽  
Normal Coordinate Analysis ◽  
Force Constants ◽  
Characteristic Set ◽  
Normal Coordinate ◽  
Mean Amplitudes Of Vibration ◽  
Symmetry Coordinates ◽  
The Mean ◽  
Energy Constants

The potential energy constants of diacetylene and dicyanoacetylene were obtained by the method of ?characteristic set of valence coordinates? of Herranz and Castano. The values of the various interaction force constants were determined without any assumptions regarding force fields. The mean amplitudes of vibration for the various characteristic bonds were calculated by Cyvin's method. It is shown that the conventional set of symmetry coordinates, usually characterized by individual chromophores, leads to abnormally large values for the force constants in the case of dicyanoacetylene. Hence a different set of symmetry coordinates taking into account the whole unit of CC bonds has to be chosen to get a reasonable set of force constants.

Potential Constants, Mean Amplitudes of Vibration, Shrinkage Constants and Coriolis Coupling Coefficients of Monohalo Acetylenes

1968 ◽  
Vol 23 (10) ◽  
pp. 1296-1299 ◽  
Author(s):  
K. Venkateswarlu ◽  
Mariamma P. Mathew
Keyword(s):  
Force Field ◽  
Mean Square ◽  
Coriolis Coupling ◽  
Coupling Coefficients ◽  
Interatomic Distances ◽  
Mean Amplitudes Of Vibration ◽  
Valence Force ◽  
Valence Force Field ◽  
Shrinkage Effect ◽  
The Mean

The potential constants are obtained for the monohaloacetylenes using the general valence force field. The theory of the mean-square amplitude matrices is applied to these molecules and the parallel and perpendicular mean-square amplitudes for the interatomic distances are calculated. The perpendicular amplitudes have been used for calculating the shrinkage effect. The Coriolis coupling coefficients are also obtained for all these molecules.

Schwingungsberechnungen der Species Ti2Cl102− , Ti2Cl9− und TiCl5− / Molecular Vibration Analysis of Ti2Cl102− , Ti2Cl9− and TiCl5−

1979 ◽  
Vol 34 (3) ◽  
pp. 362-368 ◽  
Author(s):  
A. F. Demiray ◽  
W. Brockner ◽  
B. N. Cyvin ◽  
S. J. Cyvin
Keyword(s):  
Potential Energy ◽  
Matrix Method ◽  
Vibration Analysis ◽  
Molecular Model ◽  
Molecular Vibration ◽  
Normal Coordinate ◽  
Energy Distributions ◽  
Mean Amplitudes Of Vibration ◽  
Symmetry Coordinates ◽  
The Mean

AbstractNormal coordinate analyses of the chlorotitanate ions Ti2Cl102−Ti2Cl9− - and TiCl5− have been carried out following Wilson's FG matrix method. The final force constants are given in terms of symmetry coordinates, which are thoroughly specified for a Ti2Cl9− molecular model. Assignments of the vibrational frequencies of the title compounds are proposed, and the corresponding potential energy distributions are given. The final force fields were used to calculate the mean amplitudes of vibration, of which those of TiCl5− and selected values of Ti2Cl102− andTi2Cl9− are reported.

Mittlere Schwingungsamplituden des Trithiocarbonat- und Triselenocarbonations

1966 ◽  
Vol 21 (5) ◽  
pp. 393-396 ◽  
Author(s):  
G. Nagarajan ◽  
A. Müller
Keyword(s):  
Mean Square ◽  
Mean Amplitudes Of Vibration ◽  
Symmetry Coordinates

Mean-square amplitude quantities and mean amplitudes of vibration for CS32⊖ and CSe32⊖ at 298 °K and 500 °K are computed. The method of Cyvin utilizing symmetry coordinates has been employed. A brief discussion of the results is given.

Condensed Aromatics. Part III. In-Plane Molecular Vibrations of Pyrene

1979 ◽  
Vol 34 (7) ◽  
pp. 876-886 ◽  
Author(s):  
S. J. Cyvin ◽  
B. N. Cyvin ◽  
J. Brunvoll ◽  
J. C. Whitmer ◽  
P. Klaeboe ◽  
...  
Keyword(s):  
Force Field ◽  
Molecular Model ◽  
Electron Diffraction Data ◽  
Mean Amplitudes Of Vibration ◽  
Symmetry Coordinates ◽  
Test Molecule ◽  
Out Of Plane ◽  
Complete Set ◽  
The Mean ◽  
Parameter Approximation

A new force field is developed for the in-plane vibrations of condensed aromatics using pyrene as a test molecule. Only five parameters are employed in this force field, which improves a four- parameter approximation previously investigated. Still the simple five-parameter approximation gives calculated vibrational frequencies in good agreement with those from the more elaborate Califano-Neto force field.In the course of the normal coordinate analysis the Hüekel molecular orbitals have been de­duced. The CC stretching parameters were modified by means of the calculated bond orders. A complete set of independent symmetry coordinates (both in-plane and out-of-plane) for the pyrene molecular model was developed.New experimental data from infrared and Raman spectra for pyrene are reported.Also the mean amplitudes of vibration are studied in detail. It is concluded that the simple five-parameter approximation gives reliable mean amplitudes, which undoubtedly are accurate enough for the interpretation of gas electron diffraction data.Finally the calculated frequencies and mean amplitudes of benzene are given. The mean amplitudes are again found to be very accurate in spite of some substantial inaccuracies in the frequencies.

Kraftkonstanten, mittlere Schwingungsamplituden, Coriolis-Kopplungskonstanten und thermodynamische Funktionen der Moleküle WOCl4 und WOBr4 / Force Constants, Mean Amplitudes, Coriolis Coupling Constants, Thermodynamic Functions, WOCl4 , WOBr4

1974 ◽  
Vol 29 (4) ◽  
pp. 620-623 ◽  
Author(s):  
W. Brockner ◽  
H. Hovdan ◽  
S. J. Cyvin
Keyword(s):  
Thermodynamic Functions ◽  
Ideal Gas ◽  
Force Constants ◽  
Coupling Constants ◽  
Coriolis Coupling ◽  
Mean Amplitudes Of Vibration ◽  
Amplitude Correction ◽  
Different Temperatures ◽  
Harmonic Oscillator Approximation ◽  
The Mean

A normal co-ordinate analysis of the molecules W 0Cl4 and WOBr4 has been carried out following W ilson’s FG matrix method. Valence force constants based on known (WOCl4) and estimated (WOBr4) molecular parameters have been evaluated. The results support the assignment of the known Raman spectra of W0Cl4 . Also the mean amplitudes of vibration and the perpendicular amplitude correction coefficients K have been computed for the temperatures T = 0 and T = 298 °K. Furthermore the Coriolis coupling constants of the ζz(EaxEb)- type have been determined. Some thermodynamic functions have also been calculated for an ideal gas state at one atmosphere pressure and different temperatures using the rigid rotor harmonic oscillator approximation.

IV. 1,3,5,7-Cyclooctatetraene

1970 ◽  
Vol 25 (2) ◽  
pp. 134-138 ◽  
Author(s):  
M. Traetteberg ◽  
G. Hagen ◽  
S. J. Cyvin
Keyword(s):  
Vibration Analysis ◽  
Force Fields ◽  
Force Constants ◽  
Harmonic Vibration ◽  
Interatomic Distances ◽  
Mean Amplitudes Of Vibration ◽  
Amplitude Correction ◽  
Symmetry Coordinates

A harmonic-vibration analysis for the vibrations of 1,3,5,7-cyclooctatetraene was performed. A suitable set of symmetry coordinates is specified, and the corresponding symmetry force constants for C8H8 are given. The developed force fields were used to calculate mean amplitudes of vibration for C8H8 and C8D8. Calculated perpendicular amplitude correction coefficients for the various interatomic distances are also reported.

scholarly journals Generalized Mean-Square Amplitudes of Vibration, Mean Amplitudes of Vibration, and Shrinkage Effects of Some Trigonal Bipyramidal XY5 and XY3Z2 Molecules.

1967 ◽  
Vol 21 ◽  
pp. 473-480 ◽  
Author(s):  
Jon Brunvoll ◽  
Peder Kierkegaard ◽  
Johan Santesson ◽  
Pär Holmberg ◽  
G. Eriksson ◽  
...  
Keyword(s):  
Mean Square ◽  
Mean Amplitudes Of Vibration ◽  
Trigonal Bipyramidal ◽  
Generalized Mean

Molecular Vibrations of Cubane and Its Deuterated Derivatives

1983 ◽  
Vol 38 (11) ◽  
pp. 1248-1262 ◽  
Author(s):  
S. J. Cyvin ◽  
B. N. Cyvin ◽  
J. Brunvoll
Keyword(s):  
Experimental Data ◽  
Iteration Method ◽  
Vibrational Frequencies ◽  
Force Constants ◽  
Molecular Vibrations ◽  
Mean Amplitudes Of Vibration ◽  
First Order ◽  
Amplitude Correction ◽  
Harmonic Field ◽  
Simultaneous Fitting

A harmonic field for cubane is developed by means of the following experimental data from literature: vibrational frequencies for C8H8, sym-C8H6D2, sym-C8H2D6 and C8D8, in addition to three Coriolis constants of C8H8. As a part of this analysis a new iteration method was developed for simultaneous fitting of vibrational frequencies and first-order Coriolis constants of a threedimensional symmetry block. The force constants were used to calculate the vibrational frequencies of all the twenty existing partially deuterated cubanes, in addition to the unsubstituted (C8H8) and perdeuterated (C8D8) molecules. Also the first-order Coriolis constants, mean amplitudes of vibration and perpendicular amplitude correction coefficients for selected cubane molecules are reported

scholarly journals Mean Amplitudes of Vibration and Shrinkage Effect of Boron Trihalides, Calculated from Urey-Bradley Force Constants.

1962 ◽  
Vol 16 ◽  
pp. 778-778 ◽  
Author(s):  
E. Meisingseth ◽  
A. Bye Knutsen ◽  
Bengt Lindberg ◽  
James McKay ◽  
Olof Theander ◽  
...  
Keyword(s):  
Force Constants ◽  
Mean Amplitudes Of Vibration ◽  
Shrinkage Effect
Sign in / Sign up

Export Citation Format

Share Document