Ion-momentum imaging of dissociative electron attachment dynamics in   acetylene
  We present experimental results for dissociative electron attachment to acetylene near the 3 eV $^2\Pi_g$ resonance. In particular, we use an ion-momentum imaging technique to investigate the dissociation channel leading to C$_2$H$^-$ fragments. From our measured ion-momentum results we extract fragment kinetic energy and angular distributions. We directly observe a significant dissociation bending dynamic associated with the formation of the transitory negative ion. In modeling this bending dynamic with \emph{ab initio} electronic structure and fixed-nuclei scattering calculations we obtain good agreement with the experiment. 
M. Fogle, D.J. Haxton, A.L. Landers, A.E. Orel and T.N. Rescigno
physics.chem-ph