A BEAM SCATTERING STUDY OF NONDISSOCIATIVE CHARGE-TRANSFER BETWEEN KR+ AND CH4 AT COLLISION ENERGIES BELOW 1 EV

The charge-transfer process Kr+ (CH4, Kr)CH4+ was investigated at coll ision energies of 0.45-1.18 eV in crossed beam scattering experiments. The energy transferred was found generally to be almost (within 0.05 eV) equal to the recombination energy of Kr+ (resonant energy transfer ). However, in addition a number of internal states of CH4+ is populat ed in inelastic and superelastic collisions. The width of this energy envelope depends on the scattering angle and on the collision energy, and extends to about +/-0.5 eV on both sides of the peak value. The in elasticity of small angle scattering, which increases from 1.18 to 0.4 5 eV, suggests an increasing fraction of ''sticky'' small impact param eter collisions and formation of an intermediate, Kr.CH4+.