Rotational inelasticity

Bodo E, Gianturco F A and Paesani F 2000 Testing intermolecular potentials with scattering experiments He-CO rotationally inelastic collisions Z. Phys. Chem., A/F214 1013-34... 

Pack R. T. Relation between some exponential approximations in rotationally inelastic molecular collisions, Chem. Phys. I ett. 14, 393-5 (1972). 

Connor J. N. L., Sun H., Hutson J. M. Exact and approximate calculations for the effect of potential anisotropy on integral and differential cross-sections Ar-N2 rotationally inelastic scattering, J. 

Pack R. T. Close coupling test of classical cross-sections for rotationally inelastic Ar-N2 collisions, J. Chem. Phys. 62, 3143-8 (1975). 

Rahn L. A., Palmer R. E., Koszykowski M. L., Greenhalgh D. A. Comparison of rotationally inelastic collision models for Q-branch Raman spectra of N2, Chem. Phys. Lett. 133, 513-6 (1987). 

Bonamy L., Bonamy J., Robert D., Lavorel B., Saint-Loup R., Chaux R., Santos J., Berger H. Rotationally inelastic rates for N2-N2 system from a scaling theoretical analysis of the stimulated Raman Q-branch, J. Chem. Phys. 89, 5568-77 (1988). 

Burshtein A. I., Kolomoitsev D. V., Nikitin S. Yu., Storozhev A. V. Manifestation of adiabaticity and strength of rotational inelastic collisions in time domain CARS spectra of nitrogen, Chem. Phys. 150, 231-5 (1991). 

Bulgakov Yu. I., Storozhev A. V., Strekalov M. L. Comparison and analysis of rotationally inelastic collision models describing the Q-branch collapse at high density, Chem. Phys. 177, 145-55 (1993). 

Under some circumstances the rotationally anisotropy may be even further simplified for T-R energy transfer of polar molecules like HF (41). To explore this quantitatively we performed additional rigid-rotator calculations in which we retained only the spherically symmetric and dipole-dipole terms of the AD potential, which yields M = 3 (see Figures 1, 3, and 4). These calculations converge more rapidly with increasing N and usually yield even less rotationally inelastic scattering. For example Table 2 compares the converged inelastic transition probabilities... 

Figure 3.19. Variation of the energy transfer into the surface in scattering of NO from Ag(l 11) as a function of Ee = f ccsO,-. Solid lines and solid points are for rotationally elastic scattering. /, = Jj = 0.5 and the open points are for non-state-resolved scattering experiments (and therefore also contains a contribution from rotationally inelastic scattering). From Ref. [181].

Continua. The wavefunctions of scattering and bound states have been calculated numerically in the close coupled approximation [358]. Converged partial wave expansions of the elastic scattering solutions have been calculated for pairs of angular momenta 71/2 = 00, 02, 22, 10, 30, 12, 11, and 13 at several hundred energy points. Rotationally inelastic... 

Buck, U. (1982). Rotationally inelastic scattering of hydrogen molecules and the non-spherical interaction, Faraday Discuss. Chem. Soc. 73, 187-203. 

Korsch, H.J. and Schinke, R. (1980). A uniform semiclassical sudden approximation for rotationally inelastic scattering, J. Chem. Phys. 73, 1222-1232. 

Bergmann, K., Hefter, U. and Witt, J. (1980). State-to-state differential cross sections for rotationally inelastic scattering of Na2 by He, J. 

Jeyes, S.R., McCaffery, A.J., Rowe, M.D. and Kato, H. (1977). Selection rules for collisional energy transfer in homonuclear diatomics. Rotationally inelastic collisions, Chem. Phys. Lett., 48, 91-94. 

Jones, P.L., Hefter, U., Mattheus, A., Witt, J., Bergmann, K., Muller, W., Meyer, W and Schinke, R. (1982). Angular resolved rotationally inelastic scattering of Na2-Ne Comparision between experiment and theory, Phys. Rev. A, 26, 1283-1301. 

Mattheus, A., Fischer, A., Ziegler, G., Gottwald, E. and Bergmann, K. (1986). Experimental proof of a Am -C j propensity rule in rotationally inelastic differential scattering, Phys. Rev. Lett., 56, 712-715. 

McCormack, J. and McCaffery, A.J. (1980). Collision dynamics of excited NaK. II. Rotationally inelastic energy transfer, Chem. Phys., 51, 405-416. 

Smith, N., Scott, T.P. and Pritchard, D.E. (1982). Substantial velocity dependence of rotationally inelastic collision cross section in Li -Xe, Chem. Phys. Lett., 90, 461-464. 

Figure 2 Experimental and theoretical results for the rotationally inelastic integral cross section in the LiH + He scattering system.

This does not, however, resolve the problem fully. We still have to account for the remainder of the missing flux and for the overestimation of rotational excitation. Rotational inelasticity is a sensitive probe of the molecular orientational corrugation of the PES (i.e. the corrugation in 0 and cj>) - overestimation... 

PES is strongly dependent on the molecular bond orientation, there can even be an ntj dependence of diffraction. Miura et al. [74] have shown that this leads to a difference in the rotational alignment of molecules scattered on or off-specular. However, as for rotational inelasticity, there are problems in the comparison of theoretical and experimental diffraction probabilities. 

Heijmen TGA, Korona T, Moszynski R, Wormer PES, Van der Avoird A (1997) Ab initio potential-energy surface and rotationally inelastic integral cross sections of the Ar-CH4 complex. J Chem Phys 107 902-913... 

Chapman WB, Schiffman A, Hutson JM, Nesbitt DJ (1996) Rotationally inelastic scattering in CH4 + He, Ne, and Ar State-to-state cross sections via direct infrared laser absorption in crossed supersonic jets. J Chem Phys 105 3497-3516... 

Balint-Kurti, G.G. (1975) The theory of rotationally inelastic collisions, in A.D. Buckingham and C.A. Coulson (eds.). International E.eview of Science, Series II, Vol 1, ButterworthS London, pp.286-326. 

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