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Updated: Jul 18, 2026

Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Cationic and anionic fragmentation of dichloromethane following inner-shell (Cl 1s) photoexcitation
A F Lago1, J Z Dávalos, U Kerdpin
1Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599-3290, USA. alago@lnls.br
Abstract:
The cationic and anionic fragmentation of dichloromethane (CH2Cl2) molecule have been investigated in the energy range of the Cl K shell by using synchrotron radiation, ion yield spectroscopy, and electron-ion coincidence spectroscopy. Total and partial ion-yield and mass spectra have been recorded as a function of the photon energy. We were able to identify several singly and multiply charged cationic fragments and the following anionic species: H-; C-; Cl-. The present results provide the first experimental report of negative ion formation from a molecule excited at the Cl 1s edge. In addition, our electron-ion coincidence data provide strong evidence of the preservation of molecular alignment for the photodissociation of CH2Cl2 after deep core-electron resonant excitation.
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