Charge-Transfer Cross Sections of H⁺ Ions in Collisions with Some Hydrocarbon Molecules in the Energy Range of 0.2 to 4 keV

The charge-transfer cross sections of H⁺ ions in collisions with C3H4,C3H6,C4H10 and their isomers have been measured in the energy range of 0.2 to 4 keV. They are compared with the recommended or predicted values by Janev et al. Most of the present data, except for those of C₃H₄ targets, are found to decrease with increasing the collision energy. This feature indicates that vibrational excited states of the target molecular ions produced after charge transfer might have resulted in creation of near or accidental resonant reaction channels. Based on this view point, a new empirical scaling relation is derived.