Total angular momentum and decay of unimolecular resonances IVR-mediated vibrational predissociation

Abstract

Full-dimensional wavepacket calculations are carried out on the vibrational predissociation of ArI₂. With the aid of a parallel computing strategy, we consider systems with total angular momentum quantum numbers up to J=24. Previous work for low J has shown that fragmentation occurs via a sparse limit intramolecular vibrational energy redistribution mechanism involving passage through a few intermediate dark states. Despite many more states becoming available as J is increased, this mechanism continues to dominate. Inspection of wavepacket densities and characterization of the dark states helps explain why the mechanism persists with increasing J.

References

1. T. Baer and W. L. Hase, Unimolecular Reaction Dynamics: Theory and Experiment, Oxford University Press, Oxford, 1996.
2. J. A. Blazy, B. M. DeKoven, T. D. Russell and D. H. Levy, J. Chem. Phys., 1980, 72, 2439.
3. K. E. Johnson, W. Sharfin and D. H. Levy, J. Chem. Phys., 1981, 74, 163.
4. J. J. Breen, D. M. Wilberg, M. Gutmann and A. H. Zewail, J. Chem. Phys., 1990, 93, 9180.
5. M. L. Burke and W. Klemperer, J. Chem. Phys., 1993, 98, 1797.
6. M. L. Burke and W. Klemperer, J. Chem. Phys., 1993, 98, 6642.
7. S. K. Gray, Chem. Phys. Lett., 1992, 197, 86.
8. S. K. Gray and O. Roncero, J. Chem. Phys., 1995, 99, 2512.
9. O. Roncero and S. K. Gray, J. Chem. Phys., 1996, 104, 4999.
10. O. Roncero, N. Halberstadt and J. A. Beswick, J. Chem. Phys., 1996, 104, 7554.
11. M. Bixon and J. Jortner, J. Chem. Phys., 1968, 48, 715.
12. J. A. Beswick and J. Jortner, Adv. Chem. Phys., 1981, 47, 363.
13. D. D. Evard, C. R. Bieler, J. I. Cline, N. Sivakumar and K. C. Janda, J. Chem. Phys., 1988, 89, 2829.
14. N. Halberstadt, S. Serna, O. Roncero and K. C. Janda, J. Chem. Phys., 1992, 97, 341.
15. O. Roncero, P. Villarreal, G. Delgado-Barrio, N. Halberstadt and K. C. Janda, J. Chem. Phys., 1993, 99, 1035.
16. E. M. Goldfield and S. K. Gray, Comput. Phys. Commun., 1996, 98, 1.
17. R. T. Pack, J. Chem. Phys., 1974, 60, 633.
18. Y. Sun, R. S. Judson and D. J. Kouri, 1989, J. Chem. Phys., 1900, 90, 241.
19. A. A. Buchachenko and N. F. Stepanov, J. Chem. Phys., 1996, 104, 9913.
20. B. P. Reid, K. C. Janda and N. Halberstadt, J. Chem. Phys., 1988, 92, 587.
21. R. T. Pack and G. A. Parker, J. Chem. Phys., 1987, 87, 3888.
22. E. U. Condon and G. H. Shortley, The Theory of Atomic Spectra, Cambridge University Press, Cambridge, 1935.
23. D. Kosloff and R. Kosloff, J. Comput. Phys., 1983, 52, 35.
24. S. K. Gray and D. E. Manolopoulos, J. Chem. Phys., 1996, 104, 7099.
25. V. Engel, Chem. Phys. Lett., 1992, 189, 76.
26. S. Marple Jr., Digital Spectral Analysis with Applications, Prentice-Hall, Englewood Cliffs, NJ, 1987.
27. S. K. Gray, J. Chem. Phys., 1992, 96, 6543.
28. U. Peskin, H. Reisler and W. H. Miller, J. Chem. Phys., 1994, 101, 9672.
29. N. Halberstadt, J. A. Beswick and K. C. Janda, J. Chem. Phys., 1987, 87, 3966.
30. S. K. Gray, Faraday Discuss., 1994, 97, 143.
31. C. C. Marston and G. G. Balint-Kurti, J. Chem. Phys., 1989, 91, 3571.
32. J. C. Light, I. P. Hamilton and J. V. Lill, J. Chem. Phys., 1985, 82, 1400.
33. Y. Saad, Numerical Methods for Large Eigenvalue Problems, Manchester University Press, Manchester, 1992.
34. D. C. Sorensen, SIAM J. Matrix Anal. Appl., 1992, 13, 357.
35. R. B. Lehoucq, D. C. Sorensen, P. Vu and C. Yang, ARPACK, 1995. Available from netlib@ornl.gov under the directory scalapak. See also the URL http://www.caam.rice.edu/ARPACK/ and for the software, the URL ftp://ftp.caam.rice.edu/pub/software/ARPACK.
36. M. J. Bramley and T. Carrington, J. Chem. Phys., 1994, 101, 8494.