Rydberg electron transfer to CS2: properties of the product CS2− ions

The properties of long-lived parent anions formed by electron transfer in collisions between K(np) Rydberg atoms and CS2 molecules are investigated. Collisions give rise to two groups of CS2− ions, one that undergoes electric-field-induced detachment in fields of ≲3 kV cm−1, the other requiring fields of ∼10–20 kV cm−1. Measurements using a Penning ion trap indicate that ions in both groups undergo autodetachment and radiative stabilization. The autodetachment rate for those ions that detach in low (high) fields is ∼5×102 s−1 (1.1×102 s−1). The corresponding radiative stabilization rates are ∼4.7×102 s−1 (2.8×102 s−1).