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arXiv · 0806.3401

Time-dependent photoionization of azulene: Optically induced anisotropy on the femtosecond scale

Kevin Raffael·Valerie Blanchet·Béatrice Chatel·Giorgio Turri·Bertrand Girard·Ivan Anton Garcia·Iain Wilkinson·Benjamin J Whitaker
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Abstract

We measure the photoionization cross-section of vibrationally excited levels in the S2 state of azulene by femtosecond pump-probe spectroscopy. At the wavelengths studied (349-265 nm in the pump) the transient signals exhibit two distinct and well-defined behaviours: (i) Short-term (on the order of a picosecond) polarization dependent transients and (ii) longer (10 ps - 1 ns) time-scale decays. This letter focuses on the short time transient. In contrast to an earlier study by Diau et al.22 [J. Chem. Phys. 110 (1999) 9785.] we unambiguously assign the fast initial decay signal to rotational dephasing of the initial alignment created by the pump transition.

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Kevin Raffael, Valerie Blanchet, Béatrice Chatel, Giorgio Turri, Bertrand Girard, Ivan Anton Garcia, Iain Wilkinson, Benjamin J Whitaker. 2008-06-20. Time-dependent photoionization of azulene: Optically induced anisotropy on the femtosecond scale. https://doi.org/10.1016/j.cplett.2008.06.009

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