Coriolis constants

Quadratic and cubic potential constants have been obtained from IR frequencies, isotopic shifts, inertial defects, Coriolis constants and centrifugal distortion, assuming the geometry from microwave data. The quadratic force field is characterized by four symmetry force constants F which are related to the inner force constants by the following equations... 

Note that the Coriolis constants fand f are not totally symmetric (Table 2) this is illustrated also by Figs. 7a und 7b. 

Oxyphosphorus (v) Compounds. Raman spectra of OPX3 (X = C1 or F) and SPC13 in the gas phase have been measured and analysed to give values of the Coriolis constants.334 Anisotropic e.s.r. studies on POCl3 have been interpreted in terms of a trigonal-bipyramidal structure with Cs symmetry.335... 

Thus if the vibrational dependence of the inertia defect can be determined experimentally, either from the observation of microwave spectra in the ground and excited vibrational states or from high resolution vibration/rotation spectra, then this provides information on the Coriolis constants and hence on the forms of the normal coordinates and the harmonic force field. 

Figure 12. The dependence of the quantum yield on J as calculated with Coriolis coupling for high J (cf. Fig. 10) for the lowest (top) and highest (bottom) values of the Coriolis constants derived.

The combination of a Hartree - Fock calculation and experimental information laid the groundwork for the first theoretical force field, due to Pulay et al. [10b]. In this calculation, nine parameters, which incorporated the effect of neglected electron correlation, were fitted to the observed frequencies and Coriolis constants of benzene. The accuracy of the determined fitting parameters was demonstrated by simulating the effect of electron correlation on the calculated HF force field of pyridine [34], naphthaline [35] and other benzene analogs. More elaborate calculations [33c, 33d], including a very recent high level (CCSD(T)) ob initio calculations by Zhou et al. [33d] have substantiated the scaled HF force field of Pulay et al. 

The Coriolis coupling constant ( 3 = 0.74 could be derived from the OP,RS branch separation (21.9 cm ) of Vas(GeC) in the vapor phase Raman spectrum. But 3 == 0.17 resulted from the P,R branch separation (16.3 cm ) of the same vibration in the vapor phase IR spectrum [68]. Calculations based on known geometrical data gave a P,R branch separation of 17.9 cm and the rotational constant A = 0.095 cm [98]. Coriolis constants were also calculated by approximation formulas ( 3 0.22) giving estimates of the OP,RS branch separation and the... 

D. A. Ramsay and co-workers has provided many constants for one of the excited singlet states CAJ of glyoxal, and the rotational structure within many of the vibrational levels of this state can be described with exceedingly high precision. Benzene, the subject of the present discussion, is another example where a fairly detailed description of numerous stationary aspects of both the ground and upper electronic states are now available. As a result of Callomon, Dunn, and Mills beautiful analysis of rotational band contours in the ultraviolet absorption spectrum, much is known about even the Coriolis constants for vibronic levels in the excited singlet state. Numerous other examples could be cited in which the geometries and many upper state constants in polyatomics are well known. 

RJH Clark, DM Rippon. The vapor-phase Raman spectra, Raman band contour analyses, Coriolis constants, and force constants of spherical top molecules MX4 (M = group IV element, X = F, Cl, Br, or I). J Mol Spectrosc 44 479-503, 1972. 

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