Mixing of States with the Same Symmetry in Negative Ions

Abstract

An analysis is performed of the mass spectrum of resonance electron capture by tetracyanoquinodimethane molecules, in which long-lived negative molecular ions are detected. At 3.6 eV, the ions can be attributed to an electron-excited Feshbach resonance with an admixture of a long-lived ground state whose contribution to the superposition of two states yields a measurable ion lifetime in the microsecond range.