N. Aristov et al., VIBRATIONALLY RESOLVED INELASTIC-SCATTERING AND CHARGE-TRANSFER IN H-C2H4 COLLISIONS(), The Journal of chemical physics, 99(4), 1993, pp. 2682-2694
Differential cross sections and time-of-flight spectra have been measu
red in a crossed molecular beam apparatus for inelastic scattering and
charge transfer in collisions of 30 eV protons with ethylene. High re
solution inelastic time-of-flight spectra reveal peaks corresponding t
o the fundamentals of at least two of the infrared active antisymmetri
c vibrational modes of ethylene. In the time-of-flight spectra of H at
oms resulting from charge transfer energy loss, peaks corresponding to
excitation of two electronic states of the ethylene molecular ion are
resolved. The H-atom product angular distributions are consistent wit
h a 2.0 eV potential well in the ground state potential energy surface
of the charge transfer reaction. The observations for the antisymmetr
ic vibrational modes are explained in terms of an ion-induced dipole m
echanism. Excitation of the symmetric modes is attributed to a vibroni
c coupling mechanism. An appendix provides a detailed account of the v
ibronic distributions in idealized low energy, high symmetry collision
s leading to stable C2H5+ complexes.