Mechanisms and dynamics of the metastable decay in Ar2+.

A detailed experimental as well as theoretical investigation of the properties of the metastable dissociation Ar₂⁺→Ar⁺+Ar is presented. The mass-analyzed ion kinetic energy (MIKE) scan technique has been performed using a three sector field mass spectrometer. The possible mechanisms of the metastability of Ar₂⁺ have been examined and the observed decay process is assigned to the II(1/2)_u→I(1/2)_g bound to continuum radiative transition, in agreement with earlier work. The calculation of the theoretical shape of the kinetic energy release distribution of fragment ions allowed us to construct the theoretical MIKE peak and compare it with the raw experimental data. The accuracy of various sets of potential energy curves for Ar₂⁺ is discussed, as well as the way of production of the metastable Ar₂⁺[II(1/2)_u] electronic state by electron impact. Excellent agreement between the experimental data and theoretical model has been observed. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]