Coriolis constant, interactions

This Coriolis hypothesis is borne out by the V2 dependence of all of the other vibrational fine structure constants (42. 22 7n) [5]. All of these constants are nearly independent of V2 up to V2 = 36, where they suddenly begin to change rapidly. The 92 constant, which controls the Al = 2 interaction between l = 0 and l = 2 components of the same (V, V2,v3) vibrational state, is affected by the same Al == 1 Coriolis interaction that caused the rapid variation of Bo,U2,o. Figures 10 and 11 show the nearly identical V2 dependence of q2 and Bo. o- Figure 12, which is a plot of 2(1 2) versus Bo,U2,o, shows that despite the erratic i>2 dependences of both 2 and B, the 2 versus B plot is linear. This indicates that the changes in both constants originate in the same Coriolis interaction ... 

It should be mentioned here finally that it is assumed that the rotational spectral analysis has properly accounted for centrifugal distortions in all cases and for other possible factors such as Coriolis interactions, Fermi resonances, internal rotation, etc., so that the rotational constants Ay, By and Cy of Eqs. (15) have these influences removed [16,18]. Moreover, special additional care is needed for... 

There is insufficient data to determine the six principal force constants and ten interactions in the most general quadratic valence force field for HN3. Thompson and Fletcher, however, applied a procedure of varying interaction constants to determine a set of force constants. These force constants are also listed in Table I. Coriolis coupling (caused by an acceleration directed at right angles to the particle displacement) between the parallel and perpendicular modes was not taken into account in this analysis. When frequencies only were used as constraints, it was possible to vary one interaction constant plus the principal constants, and the most significant interaction constant turned out to be that between F3 and F4. The importance of this constant has been explained by Thompson and Fletcher in terms of the following resonance structures ... 

Rotational constants, centrifugal distortion constants, rotation-vibration interaction constants, Coriolis coupling constants, anharmonic constants, and references for structural data... 

The Coriolis coupling constants in Table 11 were derived from the effect of the zero point vibration on the rotational constants through vibration-rotation interaction [20] and from an harmonic force field [21] (symmetry of vibration A, E z C3 axis). 

The vibration-rotation spectra and/or the rotational spectra in excited vibrational states provide the af constants and, when all the a/ constants are determined, the equilibrium rotational constants can be obtained by extrapolation. This method has often been hampered by anharmonic or harmonic resonance interactions in excited vibrational states, such as Fermi resonances arising from cubic and higher anharmonic force constants in the vibrational potential, or by Coriolis resonances. Equihbrium rotational constants have so far been determined only for a limited number of simple molecules. To be even more precise, one has further to consider the contributions of electrons to the moments of inertia, and to correct for the small effects of centrifugal distortion which arise from transformation of the original Hamiltonian to eliminate indeterminacy terms [11]. Higher-order time-independent effects such as the breakdown of the Bom-Oppenheimer separation between the electronic and nuclear motions have been discussed so far only for diatomic molecules [12]. 

Diatomic Molecules. For triatomic molecules there are terms involving Coriolis interactions between vibrational modes in the correction from Bg to Bz, and the theory of the preceding sections is required. For linear or for bent symmetrical XY, molecules the rotational constants of a single isotopic species are sufficient to define the molecular structure completely, and thus for such molecules spectroscopic methods are superior in precision to the electron diffraction method. Electron diffraction studies serve as a test not only of the electron diffraction technique but also of the comparability between and r%. Some examples are given in Table 4. Besides the molecules CS., CIO, and CO, for which details are given, a... 

Theoretical A values were computed using the decomposition A = Avib + cent + eieo where Ayjb is the vibrational state dependent part and Acem nd Aeiec re corrections due to the effects of centrifugal distortion and electronic interaction. The A ib part is primarily related to the Coriolis coupling constants ( 13, 23) the distortion constant igbab. and Aeiecto the... 

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