The vibronic structure of the first electronically excited state S 1 and ionic ground state D 0 of phenetole has been investigated by means of resonance enhanced multi photon ionization (REMPI) and mass analyzed threshold ionization (MATI) spectroscopy. The vibronic levels were assigned with the aid of quantum chemical calculations at the (TD)DFT level of theory and a multidimensional Franck-Condon approach. The S 1 excitation energy of phenetole has been determined to be 36370 AE 4 cm À1 (4.5093 AE 0.0005 eV). The adiabatic ionization energy was determined to be 65665 AE 7 cm À1 (8.1415 AE 0.0008 eV). The vibronic structure has been analyzed whereby the in-plane bending vibration bend shows high activity in the first excited state but is more pronounced in the ionic ground state. Moreover, a strong Duschinsky rotation effect can be observed for several D 0 S 1 transitions that causes violations of the Áv ¼ 0 propensity rule.

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3-Fluoropyridine (3-FP) has been investigated by means of two-photon resonance-enhanced multi photon ionization (REMPI), mass-analyzed threshold ionization (MATI) and one-photon vacuum-ultraviolet (VUV) MATI spectroscopy. The aim was the determination of...

<div>The radiationless decay dynamics of the S1 (nπ*) state and the 3p and 3d Rydberg states of cyclohexanone are investigated using femtosecond time-resolved time-of- flight mass spectrometry and photoelectron imaging spectroscopy. After two-photon excitation of the 3p and 3d states, an ultrafast population transfer to the 3s state is observed within < 120 fs. We ascribe this behavior to strong vibronic interactions of the excited Rydberg states with the ¹ππ* valence state that enable an ultrafast population transfer via an avoided crossing and the subsequent passage of a conical intersection between the respective electronic states. Eventually, the 3s state deactivates by internal conversion to the S₁ (nπ*) state, which in turn is found to be long-lived with a decay time of ~ 300 - 800 ps.</div>

<div>The radiationless decay dynamics of the S1 (nπ*) state and the 3p and 3d Rydberg states of cyclohexanone are investigated using femtosecond time-resolved time-of- flight mass spectrometry and photoelectron imaging spectroscopy. After two-photon excitation of the 3p and 3d states, an ultrafast population transfer to the 3s state is observed within < 120 fs. We ascribe this behavior to strong vibronic interactions of the excited Rydberg states with the ¹ππ* valence state that enable an ultrafast population transfer via an avoided crossing and the subsequent passage of a conical intersection between the respective electronic states. Eventually, the 3s state deactivates by internal conversion to the S₁ (nπ*) state, which in turn is found to be long-lived with a decay time of ~ 300 - 800 ps.</div>