Quasi-Line Phosphorescence Spectra of Dioxines at 4.2 K: Dibenzo-n-dioxine

摘要

The quasi-line phosphorescence spectra of dibenzo-n-dioxine in n-hexane and n-heptane are first obtained and then studied in detail at 4.2 K. The vibrational structure of phosphorescence spectra is analyzed; and frequencies, shape, and symmetry of the fundamental modes manifested in these spectra are determined. The symmetry of the lowest triplet state is determined, and mechanisms of the radiative T1→S0 transition in dibenzo-n-dioxine are suggested. The high degree of selectivity is noted in the case of Herzberg–Teller vibronic interactions, which is less pronounced in the case of Franck–Condon interactions.