Photoelectron-photoion momentum spectroscopy as a clock for chemical rearrangements: isomerization of the di-cation of acetylene to the vinylidene configuration.
We have used complete correlated momentum mapping of the photoelectron and heavy ion products from the dissociation of the di-cation of acetylene, induced by photoionizing the carbon K shell of one of the atoms, to map out the angular correlation between the electron and the axis of the target molecule. The (quasi-) symmetric decay is found to proceed through both acetylene and vinylidene configurations. By using the strongly peaked photoelectron emission to "start a clock," an upper limit of 60 fs is placed on the isomerization time from the acetylene to the vinylidene configuration.
Osipov
T
T
J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, KS 66506, USA.
Cocke
C L
CL
Prior
M H
MH
Landers
A
A
Weber
Th
T
Jagutzki
O
O
Schmidt
L
L
Schmidt-Böcking
H
H
Dörner
R
R