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Updated: Jun 13, 2026

Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Threshold effects in I- x CH3CN and I- x H2O cluster anion detachment: the angular distribution as an indicator of
Foster Mbaiwa1, Jie Wei, Matthew Van Duzor
1Department of Chemistry, Washington University, One Brookings Dr., Campus Box 1134 Saint Louis, Missouri 63130, USA.
Abstract:
I(-) x H(2)O and I(-) x CH(3)CN cluster anion photodetachment properties (photoelectron spectra and angular distributions) are recorded via velocity mapped photoelectron imaging for wavelengths between 270 and 340 nm, in small energy increments. These are compared with free I(-) detachment results and reveal the presence of a sharp change in the angular distribution for the (2)P(3/2) spin orbit channel in the vicinity of the (2)P(1/2) threshold. The effect is seen at this threshold in the I(-) x H(2)O cluster anion and just below threshold for I(-) x CH(3)CN. The effect is attributed to an electronic autodetachment process, which is dependent on electronic energy transfer mediated by the electron-neutral complex produced in the excitation process. These results highlight the potential of cluster anion detachment as a probe of electron-molecule interactions and in particular the sensitivity of the angular distributions to intracluster electron transfer processes.
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