SVL fluorescence spectra of sulphur dioxide

Kinetics of fluorescence decay of SO2 excited in the 2662–3273 Å region

“…Strong evidence for this is provided by the observed enhancement of the [S]o/[L]o state population ratio on excitation within the relatively unperturbed spectral region near 3226 A, attributed to the lA2 -% 1A 1 transition. We would like to point out that the tentative identification of the structure in the fluorescence emission excited within the 3150-2930 h; region [12,13] as originating from the 1B1-'A1 transition, when coupled with the present results, also supports this assignment indirectly. It may appear incongruous that absorption by SO2 in a structured region characteristic of SOz(IA2) -S02@ ' A * ) transition should yield fluorescence which on analysis appears to support the 'B1 state as the emitter.…”

“…(S) state which contribute to this emission were attributed tentatively to the lB1 and lA2 states of S 0 2 , respectively. McDonald and coworkers concluded that the state of SO2 could be populated even at wavelengths as short as 3350 A, in seeming contradiction of the tentative band origin assignment from the data of Hamada and Merer [lo] and Shaw and coworkers [12,13]. It was not possible to choose between alternative mechanisms of independent generation and decay of the L and S species and that involving generation of one from the other by way of first-order or second-order collisionally perturbed processes.…”

Excited state dynamics in SO2. I. Bound state relaxation studied by time-resolved photoelectron-photoion coincidence spectroscopy

“…At excitation energies between 4.03 and 4.28 eV, the pump pulses span two or more Clements bands, preparing different degrees of symmetric stretch and bending mode excitation in the initially excited vibrational states. 5,6,13,14,22 Specifically, the Clements C and D, F, and G and N, N , and O bands were excited with the 4.03 eV, 4.12 eV, and 4.28 eV pump photons, respectively. The electronic and vibrational nature of the excited state evolved in time during and following the excitation process.…”

“…2,3 It is now [4][5][6][7][8][9][10][11][12][13][14][15][16] and perturbations by the underlying triplet manifold, 2,3,[17][18][19] respectively. It is these interactions that are responsible for the complex absorption profile associated with the first excited singlet states of SO 2 shown in Fig.…”

Kinetic studies on state-state coupling and collisional quenching of excited sulfur dioxide

“…The latter is intensively perturbed through Renner -Teller coupling with the ground state [7] and excitation into the B 1 B 1 state is associated with a weak underlying "quasi-continuum" in the absorption spectrum. The studies of single vibronic level fluorescence spectra by Shaw et al [8,9] gave credence to the explanation that the bulk of the emission is due to the B 1 B 1 levels spread among the A 1 A 2 levels.…”