The absorption spectrum of carbonyl selenide: Sub-Rydberg transitions

Abstract

The three absorption systems of carbonyl selenide observed at longer wavelengths have been vibrationally analyzed. The 2500 Å system has its origin band at 39 953 cm −1, and shows prominent progressions in the bending mode ν 2 in both the ground and excited states. The upper state of this transition is assigned as the 1 A″ component of the bent 1Δ state arising from the valence π 3 π configuration. The 2000 Å system also shows progressions in ν 2, and the upper state is assigned as bent 1 A″ ( 1Σ −) also arising from the valence π 3 π configuration. The origin of the transition is at ∼49 000 cm −1. The 1800 Å system, with origin at 55 595.7 cm −1 for OC 80Se, shows evidence of Renner-Teller splittings in the upper state. The latter is assigned as 1Π, with Renner-Teller parameters ϵ = 0.041, ω 2′ = 409 cm −1. This state is believed to have partial Rydberg character derived from the π 3(5 sσ) electron configuration.