Direct observation of the femtosecond nonradiative dynamics of azulene in a molecular beam: The anomalous behavior in the isolated molecule

Using femtosecond-resolved mass spectrometry in a molecular beam, we report real-time observation of the nonradiative, anomalous dynamics of azulene. We studied both S_2 and S_1 state dynamics. The motion of the wave packet in S_1 involves two time scales, a dephasing time of less than 100 fs and a 900±100 fs internal conversion. We discuss the dynamical picture in relation to the molecular structures and the conical intersection, and we compare with theory.

[1]  E. Riedle,et al.  Comprehensive measurement of the S1 azulene relaxation dynamics and observation of vibrational wavepacket motion , 1999 .

[2]  John D. Roberts,et al.  Femtosecond dynamics of valence-bond isomers of azines: transition states and conical intersections , 1998 .

[3]  Barry R. Smith,et al.  Mixed state `on the fly' non-adiabatic dynamics: the role of the conical intersection topology , 1998 .

[4]  Thom Vreven,et al.  The Azulene S1 State Decays via a Conical Intersection: A CASSCF Study with MMVB Dynamics , 1996 .

[5]  B. Wagner,et al.  Subpicosecond vibrational relaxation of the S1 states of azulene and guaiazulene in solution , 1995 .

[6]  B. Wagner,et al.  The effect of solvent viscosity on the population relaxation times of the S1 state of azulene and related compounds , 1993 .

[7]  B. Wagner,et al.  Radiationless decay of the S2 states of azulene and related compounds: solvent dependence and the energy gap law , 1992 .

[8]  M. Tomita,et al.  Femtosecond vibrational relaxation measurement of azulene using temporally incoherent light , 1992 .

[9]  D. Schwarzer,et al.  S1-Lifetime of azulene in solution. , 1991 .

[10]  S. K. Kulkarni,et al.  Excess energy dependence of internal conversion in the S1 state of azulene , 1988 .

[11]  Toshinori Suzuki,et al.  S1 .rarw. S0 transition of jet-cooled azulene studied by population labeling spectroscopy , 1987 .

[12]  G. Leach,et al.  Picosecond dynamics of intramolecular vibrational redistribution in the S2 state of jet-cooled azulene , 1987 .

[13]  J. Jortner,et al.  Spectroscopic manifestation of intramolecular relaxation of azulene in supersonic jets , 1984 .

[14]  A. Zewail,et al.  Direct picosecond time resolution of dissipative intramolecular vibrational-energy redistribution (IVR) in isolated molecules , 1984 .

[15]  R. Hochstrasser,et al.  Resonance fluorescence, Raman spectra and relaxation of single vibronic levels in the condensed phase: Azulene in naphthalene , 1979 .

[16]  E. Ippen,et al.  Radiationless relaxation processes in azulene , 1978 .

[17]  E. Ippen,et al.  Picosecond dynamics of azulene , 1977 .

[18]  A. Penzkofer Relaxation dynamics of the first excited electronic singlet state of azulene in solution , 1976 .

[19]  S. Schneider,et al.  Ultrafast electronic relaxation in the S1 state of azulene and some of its derivatives , 1976 .

[20]  R. Hochstrasser,et al.  Moderately high resolution fluorecence spectrum of the S1 → S0 transition of azulene , 1974 .

[21]  G. Small,et al.  Vibronic effects in the 7000 Å state of azulene , 1974 .

[22]  J. Jortner,et al.  Laser Excited Emission Spectroscopy of Azulene in the Gas Phase , 1972 .

[23]  R. Hochstrasser,et al.  Spectral manifestations of nonradiative processes in azulene , 1972 .

[24]  P. Rentzepis Emission from the lowest singlet and triplet states of azulene , 1969 .

[25]  E. Drent,et al.  Direct measurement of S–T crossing relaxation time in azulenes , 1968 .

[26]  Peter M. Rentzepis,et al.  Direct measurements of radiationless transitions in liquids , 1968 .

[27]  M. Kasha,et al.  Confirmation of the Anomalous Fluorescence of Azulene , 1956 .

[28]  H. C. Longuet-Higgins,et al.  Anomalous Light Emission of Azulene , 1955 .

[29]  Ahmed H. Zewail,et al.  Femtochemistry: Ultrafast Dynamics of the Chemical Bond , 1994 .

[30]  B. Wagner,et al.  Subpicosecond pump–probe measurements of the electronic relaxation rates of the S1 states of azulene and related compounds in polar and nonpolar solvents , 1993 .

[31]  J. Jortner,et al.  Azulene Revisited: Picosecond Decay of the S1 State in the Gas Phase and in Solution , 1977 .

[32]  R. Levine,et al.  Molecular energy transfer , 1976 .

[33]  G. Hunt,et al.  Spectrum of azulene: Part II. The 7000-A and 3500-A absorption systems , 1962 .