The S₀→S₁ cavity ring-down absorption spectrum of jet-cooled azulene: dependence of internal conversion on the excess energy

Abstract

The S₀→S₁ cavity ring-down (CRD) absorption spectrum of jet-cooled azulene is reported in the spectral region between 14275 and 17300 cm^-1. The excess energy dependence of the fast internal conversion rate k_ic (S₁S₀) was investigated in the frequency domain by evaluating the linewidths of vibronic states up to excess energies of ∽hc×2500 cm^-1. A value for the S_1,0 lifetime of ≈2.6±0.4 ps was found. New experimental evidence for a conical intersection of the S₀ and S₁ potentials at ≈2100±100 cm^-1 was found. The possibility of azulene being one of the carriers of the diffuse interstellar bands (DIB) is briefly discussed.

References

1. M. B. Beer and H. C. Longuet-Higgins, J. Chem. Phys., 1955, 23, 1390.
2. D. Huppert, J. Jortner and P. M. Rentzepis, J. Chem. Phys., 1972, 56, 4826.
3. G. D. Gillispie and E. C. Lim, J. Chem. Phys., 1978, 68, 4578.
4. T. M. Woudenberg, S. K. Kulkarni and J. E. Kenny, J. Chem. Phys., 1988, 89, 2789.
5. P. M. Rentzepis, Chem. Phys. Lett., 1968, 3, 717.
6. A. Amirav and J. Jortner, J. Chem. Phys., 1984, 81, 4200.
7. T. Suzuki and M. Ito, J. Phys. Chem., 1987, 91, 3537.
8. S. K. Kulkarni and J. E. Kenny, J. Chem. Phys., 1988, 89, 4441.
9. G. R. Hunt and I. G. Ross, J. Mol. Spectrosc., 1962, 9, 50.
10. J. P. Heritage and A. Penzkofer, Chem. Phys. Lett., 1976, 44, 76.
11. E. P. Ippen, C. V. Shank and R. L. Woerner, Chem. Phys. Lett., 1977, 46, 20.
12. C. V. Shank, E. P. Ippen, O. Teschke and R. L. Fork, Chem. Phys. Lett., 1978, 57, 433.
13. D. Schwarzer, J. Troe and J. Schroeder, Ber. Bunsen-Ges. Phys. Chem., 1991, 95, 933.
14. B. D. Wagner, M. Szymanski and R. P. Steer, J. Chem. Phys., 1993, 98, 301.
15. A. J. Wurzer, T. Wilhelm, J. Piel and E. Riedle, Chem. Phys. Lett., 1999, 299, 296.
16. M. J. Bearpark, F. Bernardi, S. Clifford, M. Olivucci, M. A. Robb, B. R. Smith and T. Vreven, J. Am. Chem. Soc., 1996, 118, 169.
17. S. Klein, M. J. Bearpark, B. R. Smith, M. A. Robb, M. Olivucci and F. Bernardi, Chem. Phys. Lett., 1998, 292, 259.
18. A. O'Keefe and D. A. G. Deacon, Rev. Sci. Instrum., 1988, 59, 2544.
19. M. D. Wheeler, S. M. Newman, A. J. Orr-Ewing and M. N. R. Ashfold, J. Chem. Soc., Faraday Trans., 1998, 94, 337.
20. A. A. Ruth, T. Fernholz, R. P. Brint and M. W. D. Mansfield, Chem. Phys. Lett., 1998, 287, 403.
21. M. Schutz, U. Heitmann and A. Hese, Appl. Phys. B, 1995, 61, 0339.
22. D. Romanini, 1998, private communication.
23. R. M. Hochstrasser and C. A. Nyi, J. Chem. Phys., 1979, 70, 1112.
24. G. J. Small and S. Kusserow, J. Chem. Phys., 1974, 60, 1558.
25. F. Negri and M. Z. Zgierski, J. Chem. Phys., 1993, 99, 4318.
26. F. W. Birss and D. A. Ramsay, Comput. Phys. Commun., 1984, 38, 83.
27. R. M. Hochstrasser and T.-Y. Li, J. Mol. Spectrosc., 1972, 41, 297.
28. A. Amirav, U. Even and J. Jortner, Chem. Phys. Lett., 1980, 72, 21.
29. M. Pirotta, F. Güttler, H. Gygax, A. Renn, J. Sepiol and U. Wild, Chem. Phys. Lett., 1993, 208, 379.
30. E. W.-G. Diau, S. De Feyter and A. H. Zewail, J. Chem. Phys., 1999, 110, 9785.
31. M. Olivucci, 1999, private communication.
32. S. Grimme, Chem. Phys. Lett., 1993, 201, 67.
33. D. A. Kirkwood, H. Linnartz, M. Grutter, O. Dopfer, T. D. Motylewski, M. Pachkov, M. Tulej, M. Wyss and J. P. Maier, Faraday Discuss., 1998, 109, 109.
34. J. R. Miles and P. J. Sarre, J. Chem. Soc., Faraday Trans., 1992, 88, 1075; J. R. Miles and P. J. Sarre, J. Chem. Soc., Faraday Trans., 1993, 89, 2269.
35. F. M. Johnson, Bull. Am. Astron. Soc., 1991, 23, 933.
36. H. W. Kroto, J. R. Heath, S. C. O'Brien, R. F. Curl and R. E. Smalley, Nature, 1985, 318, 162.
37. F. Salama, E. L. O. Bakes, L. J. Allamandola and A. G. G. M. Tielens, Astrophys. J., 1996, 458, 621.
38. G. P. Van der Zwet and L. J. Allamandola, Astron. Astrophys., 1985, 146, 81.
39. A. Léger and L. B. d'Hendecourt, Astron. Astrophys., 1985, 146, 76.
40. A. G. G. M. Tielens and T. P. Snow, The diffuse interstellar bands, Kluwer Academic Publishers, Dordrecht, Boston, London, 1995.
41. P. Jenniskens and F.-X. Désert, Astron. Astrophys. Suppl. Ser., 1994, 106, 39.
42. G. H. Herbig, Annu. Rev. Astrophys., 1995, 33, 19.
43. D. Romanini, L. Biennier, F. Salama, A. Kachanov, L. J. Allamandola and F. Stoeckel, Chem. Phys. Lett., 1999, 303, 165.
44. A. Goeres, 1999, private communication.