The Huggins bands of ozone

Abstract

The vibrational analysis of the Huggins band system of O3 is reexamined and the electronic transition identified as 1A1 ← 1A1 on the basis that 1–0 and 0–1 transitions in ν3 are widely distributed in the spectrum. Franck–Condon analysis indicates that the 2lA1 state has r = 1.360 Å, θ = 102.4°, corresponding to a longer bond and sharper angle than the ground state structure (r0 = 1.279 Å, θ0 = 116.8°). Estimates of the upper state decay time (2 × 10−13 s) and the f-value of the transition from the ground state (~ 1 × 10−4) are presented. The upper state potential well is considered to result from the avoided crossing of the X1A1(4π) and 21A1(6π) diabatic surfaces.