Abstract
FOR chemical reactions in solution, the solvent exerts an important influence on the elementary processes of bond making and breaking. The solvent may, for example, enhance bond formation by trapping reactive species in a 'solvent cage' on the reaction timescale1, or it may act as a 'chaperone' that stabilizes energetic species2. Ultrafast reaction dynamics in solvent shells can be probed using laser spectroscopic techniques developed to resolve atomic motion on the femtosecond (fs) timescale3. Here we report on a study of the femtosecond dynamics of the dissociation of neutral iodine molecules encaged in clusters of around 40–150 argon atoms, which form a solvent shell4–6. We find that, when dissociation occurs from the A-type excited electronic state of I2, the iodine atoms exhibit coherent motion on a sub-picosecond (<10−12s) timescale, rebounding from the 'frozen' solvent cage and recombining. The 'hot' I2 molecule is then cooled over by collisions with the argon atoms. We provide support for these interpretations using molecular-dynamics simulations. Dissociation from the B state, meanwhile, involves slower bond-breaking and slower recombination of the fragments—there is no coherent 'rebound' from the solvent cage. The dissociation pathway therefore depends critically on the timescale of bond breaking relative to that of solvent rearrangement.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Frank, J. & Rabinovitch, E. Trans. Faraday Soc. 30, 120–131 (1934).
Porter, G. & Smith, J. A. Proceedings Royal Soc. A 261, 28–37 (1961).
Zewail, A. H. Faraday Discuss. Chem. Soc. 91, 207–237 (1991).
Saenger, K. L., McClelland, G. M. & Herschbach, D. R. J. phys. Chem. 85, 3333–3337 (1981).
Jortner, J., Scharf, D., Ben-Horin, N., Evan, U. & Landman, U. in Proc. int. School of Physics (ed. Scholes, G.) 43–98 (North-Holland, Amsterdam, 1990).
Berry, R. S. in Proc. int. School of Physics (ed. Scholes, G.) 3–22 (North-Holland, Amsterdam, 1990).
Papanikolas, J. M. et al. J. phys. Chem. 95, 8028–8040 (1991).
Breen, J. J. et al. J. chem. Phys. 92, 805–807 (1990).
Gutmann, M., Willberg, D. M. & Zewail, A. H. J. chem. Phys. 97, 8048–8059 (1992).
Potter, E. D., Liu, Q. & Zewail, A. H. Chem. Phys. Lett. 200, 605–614 (1992).
Papanikolas, J. M. et al. J. chem. Phys. 97, 7002–7005 (1992).
Baumert, T., Engel, V., Meier, C. & Gerber, G. Chem. Phys. Lett. 200, 488–494 (1992).
Wei, S., Purnell, J., Buzza, S. A., Stanley, R. J. & Castleman, A. W. Jr J. chem. Phys. 97, 9480–9482 (1992).
Schreiber, E., Kühling, H., Kobs, K., Rutz, S. & Wöste, L. Ber. Bunsenges. phys. Chem. 96, 1301–1305 (1992).
Amar, F. G. & Berne, B. J. J. phys. Chem. 88, 6720–6727 (1984).
Alimi, R., Gerber, R. B., McCaffray, J. G., Huntz, H. & Schwentner, N. Phys. Rev. Lett. 69, 856–859 (1992).
Stace, A. J. J. Chem. Soc. Farad. Trans. II 77, 2105–2110 (1981).
Fei, S., Zheng, X., Heaven, M. & Tellinghuisen, J. J. chem. Phys. 97, 6057–6063 (1992).
Valentini, J. J. & Cross, J. B. J. chem. Phys. 77, 572–573 (1982).
Beswick, J. A., Monot, R., Phillippoz, J.-M. & van den Bergh, H. J. chem. Phys. 86, 3965–3967 (1987).
Burke, M. L. & Klemperer, W. J. chem. Phys. 98, 1797–1809 (1993).
Schroeder, J. & Troe, J. A. Rev. phys. Chem. 38, 163–190 (1987).
Harris, A. L., Brown, J. K. & Harris, C. B. A. Rev. phys. Chem. 39, 341–366 (1988).
Scherer, N. F., Ziegler, L. D. & Fleming, G. R. J. chem. Phys. 96, 5544–5547 (1992).
Dardi, P. S. & Dahler, J. S. J. chem. Phys. 98, 363–372 (1993).
Bowman, R. M., Dantus, M. & Zewail, A. H. Chem. Phys. Lett. 161, 297–302 (1989).
Gruebele, M. & Zewail, A. H. J. chem. Phys. 98, 883–902 (1993).
Farges, J., de Ferandy, M. F., Raoult, B. & Torchet, G. J. chem. Phys. 84, 3491–3501 (1986).
Tellinghuisen, J. J. chem. Phys. 58, 2821–2834 (1973).
Nesbit, D. J. & Hynes, J. T. J. chem. Phys. 77, 2130–2143 (1982).
Joly, A. G., Ruhman, S., Kohler, B. & Nelson, K. A. Springer Ser. chem. Phys. 48, 506–510 (1988).
Benjamin, I., Banin, U. & Ruhman, S. J. chem. Phys. 98, 8337–8340 (1993).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Liu, Q., Wang, JK. & Zewail, A. Femtosecond dynamics of dissociation and recombination in solvent cages. Nature 364, 427–430 (1993). https://doi.org/10.1038/364427a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/364427a0
This article is cited by
-
Atomistic characterization of the active-site solvation dynamics of a model photocatalyst
Nature Communications (2016)
-
Sub-10 fs laser pulses with repetition rate of 1.1 GHz by a Ti: sapphire oscillator
Chinese Science Bulletin (2009)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.