Photochemistry of CFCl: Quenching of Charged Fragments Is Caused by Nonadiabatic Effects.

For the first time, high-level multireference electronic structure calculations have been performed to study the photochemistry of CFCl, allowing a comprehensive interpretation and assignment of experimental data concerning fluorescence, ion-pair formation, and generation of CF fragments in several electronic states. All studied dissociation channels correlate either with Cl or Cl in the ground state. On the other hand, a CF fragment can be generated either in the ground or excited state.

Photochemistry of CH3Cl: Dissociation and CH···Cl Hydrogen Bond Formation.

State-of-the-art electronic structure calculations (MR-CISD) are used to map five different dissociation channels of CH3Cl along the C-Cl coordinate: (i) CH3(X̃(2)A2″) + Cl((2)P), (ii) CH3(3s(2)A1') + Cl((2)P), (iii) CH3(+)((1)A1') + Cl(-)((1)S), (iv) CH3(3p(2)E') + Cl((2)P), and (v) CH3(3p(2)A2″) + Cl((2)P). By the first time these latter four dissociation channels, accessible upon VUV absorption, are described. The corresponding dissociation limits, obtained at the MR-CISD+Q level, are 3.