Coriolis coupling constants

The six fundamental vibrational frequencies for SeF and TeFe are given in Table XII (21,37,38,103). Force constants for SeFs, calculated with the frequencies from vapor-phase Raman spectra (21) and using isotope shifts and Coriolis coupling constants as additional data (103), are listed in Table XIII in comparison to TeFg (1,24,104,125,139). 

There is no uniform convention for denoting the internal vibrational angular momentum j, n, p and G have all been used. For symmetric top and linear molecules the component of j in the symmetry axis is always denoted by the quantum number /, where l takes values in the range — v < l 4i in steps of 2. The corresponding component of angular momentum is actually l h, rather than Ih, where f is a Coriolis coupling constant. 

There have been many force contact treatments (see for example ref. 573) and determinations of Coriolis coupling constants.574 The use of transitions within the Os04 molecule as high-precision frequency standards using C02 lasers has been described in a number of publications.575,576... 

Due to the rotational structure as well as the so-called hot hand absorptions (Sec. 2.5.3), the contour of a rovibrational band depends on the temperature. Today it is possible to determine molecular constants such as moments of inertia, Coriolis coupling constants, centrifugal distortion constants, and anharmonicity coefficients by FTIR as precisely as possible in order to calculate the intensity and shape of an absorption band. In such a simulation process the temperature may be used as a parameter. The results can be compared to the experimental spectra and the temperature may be deduced by fitting the calculated to the observed bands. This is possible with IR as well as with Raman bands. A review of curve fitting procedures and their limitations has been given by Maddams (1980). 

The present stage is suitable for the introduction of the Coriolis coupling constants, f%k 63, 64). This may seem curious, but it is in accordance with the fact that these constants are appropriate only when rectilinear coordinates are involved. This will be further discussed below in relation to the vibration-rotation part of the G-matrix. Here it is convenient to give a general definition,... 

Functions of p corresponding to Coriolis-coupling constants are still determined by Eq. (3.47) which cannot be further simplified. 

There have been a large number of determinations of molecular force constants, mean amplitudes of vibration, bond asymmetry parameters, Coriolis coupling constants (and inertia defects) and centrifugal distortion constants [146,152,259,271,304,581,840,1221,1222,1278,1312, 1416,1448,1449,1549,1550,1575-1578,1587,1618,1671,1682,1806,1807,1858,1931,1961,1984,2021,2045, 2108,2109-2111,2167a], as well as a determination of the atomic potential energy distribution... 

In these equations, harmonic frequency of the normal coordinate Q/ and is a Coriolis coupling constant. is the equilibrium moment... 

In addition to isotope frequency shifts, mean amplitudes of vibration, Coriolis coupling constants, centrifugal distortion constants, and so forth may be used to refine the force constants of small molecules (see Ref 81). 

Coriolis coupling constants have been calculated from the vapor-phase Raman spectra of some XY -type molecules [1197]. 

Force constants, Coriolis coupling constants, and mean amplitudes of vibration of InCl have also been calculated from previously reported vibrational data. The stretching force constants of the isoelectronic sequence are in the following order InCl < SnClg" < SbCl. ... 

A vapour-phase Raman spectrum of borazine has been obtained under medium resolution. Band contours of the E" fundamentals were measured, enabling estimates to be made of the Coriolis coupling constants Ct- It is the first time that a reasonably complete assignment has been made of the gas-phase vibrational wavenumbers of BaNaHs. ... 

Bkkf are called the Coriolis coupling constants. They couple the normal modes perpendicular to the IRC. 

The vibrational adiabatic potential Vadiab was created for a given set of the vibrational quantum numbers Vk, fixed during the reaction process. Therefore, it is impossible to exchange energy between the vibrational modes (we assume, therefore, that the Coriolis coupling constants Bkk = 0), as well as between the vibrational modes and the reaction path (we assume that the curvature coupling constants Bks = 0). This would mean a change of Vk s. 

Fig. 14.13. The reaction H2 -I- OH - H2O -I- H. The Coriolis coupling constants Bjiji l S) as functions of s. A high value of means that close to reaction coordinate the changes of the 1-th normal mode eigenvector resemble eigenvector k. Source T. Dunning, Jr. and E. Kraka, from Advances in Molecular Electronic Structure Theory, ed. T. Dunning, Jr., JAI Press, Greenwich. CT (19891. courtesy of the authors.

---