ROTATION-VIBRATION TRANSFER

McCaffery A J 1999 Quasiresonant vibration-rotation transfer a kinematic interpretation J. Chem. Phys. Ill 7697... 

An additional result of Chen and Moore s study is that a considerable portion, perhaps nearly all, of the vibration-rotation transfer in HC1 is intramolecular The vibrator leaves the collision with the major portion of... 

This computational routine for predicting state-to-state probabilities has been shown to give quantitative agreement with experiment for a wide variety of collision-induced processes. These include rotational transfer (RT) [24, 26, 36, 38—40], i.e., state change within a vibrational manifold, vibration-rotation transfer (VRT) [41, 42], i.e., transitions between vibrational states and electronic energy transfer [43], i.e., transitions between discrete levels of different electronic states. An example is given in Fig. 6 in which the calculated data were computed using the... 

While these observations would be hard to explain in terms of multiphonon relaxation, they are readily understood consequences of the vibration — rotation transfer model. Isotopic substitution will change not only the vibrational frequency of the guest but also the spacing of the rotational levels, and will modify the localized phonon structure. Whereas the vibrational spacing is proportional to the square root of reduced mass, the rotational constant changes even faster, linearly in fi. As a consequence, the closest rotational level to i = 1 is 7= 13 in NH and 7= 16 in ND. Thus, in spite of a smaller vibrational spacing, the deuteride relaxation is a higher order and hence less efficient process. 

Stewart, B., Magill, P.D., Scott, T.P., Derouard, J., and Pritchard, D.E., Quasiresonant vibration-rotation transfer in atom-diatom collisions, Phys. Rev. Lett, 60, 282, 1988. 

McCaffery,A.J., Vibration-rotation transfer in molecular super rotors,/. Chem. Phys., 113, 10947,2000. 

Resonant rotational to rotational (R-R) energy transfer may have rates exceeding the Leimard-Jones collision frequency because of long-range dipole-dipole interactions in some cases. Quasiresonant vibration to rotation transfer (V-R) has recently been discussed in the framework of a simple model [57]. 

My own research efforts [4] have, for many years, involved taking into account such non-Bom-Oppen-heimer couplings, especially in cases where vibration/rotation energy transferred to electronic motions causes... 

Kreutz T G and Flynn G W 1990 Analysis of translational, rotational, and vibrational energy transfer in collisions between COj and hot hydrogen atoms the three dimensional breathing ellipse model J. Chem. Phys. 93 452-65... 

SCHWENKE TRUHLAR Vibrational Rotational Energy Transfer 177... 

Fig. 9. Incidence energy dependence of the vibrational state population distribution resulting when NO(u = 12) is scattered from LiF(OOl) at a surface temperature of (a) 480 K, and (b) 290 K. Relaxation of large amplitude vibrational motion to phonons is weak compared to what is possible on metals. Increased relaxation at the lowest incidence energies and surface temperatures are indicators of a trapping/desorption mechanism for vibrational energy transfer. Angular and rotational population distributions support this conclusion. Estimations of the residence times suggest that coupling to phonons is significant when residence times are only as long as ps. (See Ref. 58.)...

Relaxation processes e. g. rotational isomerisation or vibrational energy transfer. 

---