Vibrational spectroscopy and state-specific dissociation dynamics for vinyl chloride cation in the state

(C2H3Cl+)-Cl-35 in the ground vibronic state was generated by one-photon mass-analyzed threshold ionization spectrometry, and its photodissociation in the 461-406 nm range was investigated. Ionization energy to the ground state of (C2H3Cl+)-Cl-35 was 10.0062 +/- 0.0006 eV while its (B)over tilde state onset was higher by 2.7456 +/- 0.0003 eV. A vibrational spectrum of the cation in the (B)over tilde state obtained by recording the product ion yield as a function of wavelength was analyzed by referring to the quantum chemical results at the TDDFT/B3LYP/6-311++(df,pd) level. Analysis of product time-of-flight profiles recorded with different laser polarization angles showed that the dissociation pathway for the cation in the (B)over tilde state changed with the vibrational energy, from internal conversion to (X)over tilde and statistical dissociation therein to curve crossing to (C)over tilde and repulsive dissociation therein. (B)over tilde -> (C)over tilde curve crossing seemed to occur along a direction close to the C-Cl bond stretch.