The CX transition in CaKr+ and CaAr+

An electronic transition in the isolated CaKr+ ion with an origin at 14217 cm−1 has been observed in the resonant photodissociation spectrum. A short vibrational progression yields excited state vibrational constants of ω′e = 60 cm−1 and ωex′e = 2.78 cm−1 and a diabatic binding energy of 330 ± 100 cm−1. The excited state in this transition arises from the Ca+3p63d[2D] + Kr[1S] atomic limit and is tentatively assigned as a 2Σ+ state. A single weak hot band feature places the ground state vibrational frequency, ΔG″12, at 74 cm−1. The analogous transition in CaAr+ has also suffered analysis. The X 2Σ+ ground state of the CaKr+ ion is bound by 840 ± 100 cm−1 almost the same as that found for CaAr+, 890 ± 100 cm−1.