Single-electron capture collisions of ground and metastable N2+.ions with atomic and molecular gases

Abstract

Translational energy spectroscopy, using a double-focusing mass spectrometer is used to study energy-loss/gain spectra for the single electron capture collisions of 6 keV N2+. ions with atomic (He, Ne, Ar, Kr, Xe) and molecular (N2, H2) target gases. The product states are identified by energy defect analysis. With all collision pairs, reaction channels have been observed which indicate the presence of the long-lived metastable state of N2+.(2p2 4P12/) in the incident beam. Comparison with previous data has shown that the fraction of this metastable state is higher in the present data. The measured data show that the probability of electron capture is greatest where there is a crossing of the potential energy curves for the initial and final states which occurs at internuclear distances between 4 and 7 au. New data are presented for Kr, Xe and N2 target gases.