Partial charge transfer of doubly charged ions

Abstract

Measurements of the partial charge transfer cross-sections for doubly charged ions X$^{2+}$ + Y $\rightarrow $ Y$^{+}$ + X$^{+}$ are described for C$^{2+}$, N$^{2+}$, A$^{2+}$ in He, Ne, A, and the results are discussed in terms of divergence from near-adiabatic conditions caused by the crossing of potential energy curves. The single endothermic case C$^{2+}$ in He behaves adiabatically; all the others, which are exothermic, show large cross-sections at low energies. In the case A$^{2+}$ in A there is a contribution from double charge transfer, which cannot be distinguished experimentally from partial charge transfer.