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Updated: Aug 2, 2026

Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Dynamics of low-energy electron attachment to formic acid
T N Rescigno1, C S Trevisan, A E Orel
1Chemical Sciences, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, USA.
Abstract:
Low-energy electrons (<2 eV) can fragment gas phase formic acid (HCOOH) molecules through resonant dissociative attachment processes. Recent experiments have shown that the principal reaction products of such collisions are formate ions (HCOO-) and hydrogen atoms. Using first-principles electron scattering calculations, we have identified the responsible negative ion state as a transient pi* anion. Symmetry considerations dictate that the associated dissociation dynamics are intrinsically polyatomic: a second anion surface, connected to the first by a conical intersection, is involved in the dynamics and the transient anion must necessarily deform to nonplanar geometries before it can dissociate to the observed stable products.
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