Gas-phase dynamics of spiropyran and spirooxazine molecules.
The gas-phase dynamics of two classes of photochromic molecules, three spiropyrans and one spirooxazine, have been investigated here using both time-resolved mass spectrometry and photoelectron spectroscopy approaches. It is, to our knowledge, the first gas-phase experiment done of these kinds of molecules. The molecules are excited at 266 nm and probed at 800 nm. The comparison of the dynamics of these four molecules has been used to propose a sequential photoisomerization mechanism involving four steps occurring in the first 100 ps. Each of these steps is discussed and related to the observed condensed-phase dynamics and to theoretical calculations.
Poisson
Lionel
L
Laboratoire Francis Perrin, CEA/DSM/DRECAM/SPAM-CNRS URA 2453, DSM CEA Saclay, 91191 Gif-sur-Yvette Cedex, France. lionel.poisson@cea.fr
Raffael
Kevin D
KD
Soep
Benoît
B
Mestdagh
Jean-Michel
JM
Buntinx
Guy
G