On the vibronic structure of the S↔S1 transitions in azulene

Abstract

Articles you may be interested in S 0↔S 1 transition of transβmethyl styrene: Vibronic structure and dynamicsThe vibronic structure of the S 0↔S 1 and S 0↔S 2 transitions in simple oligomers of thiopheneThe semiempirical (quantum chemical consistent force fieldhr-electron and complete neglect of differential overlap/spectroscopic parametrization) and ab initio methods are used to study the vibronic structure of the optical transitions between the So and SI states of azulene. It is shown that although the excited state is described quite well as arising from the promotion of one electron from the highest occupied molecular orbital to the lowest unoccupied one, the inclusion of doubly excited configurations in description of the wave functions of the two states in question is essential for a proper characterization of the geometry change upon electronic excitation and, therefore, for the resulting Franck-Condon structure of the absorption and emission spectra. The vibronically induced intensities of the b 2 fundamentals in the two spectra are calculated and compared with the experimental data, and the problem of correlation between the b 2 modes in the two states is solved.4318

Vibronic coupling simulations for linear and nonlinear optical processes: Theory

“…Evaluation of those integrals is facilitated by writing the normal coordinates in terms of the creation and annihilation operators, 21 via Eq. (7). For the multidimensional wavefunctions considered here, the creation and annihilation operatorsb † a andb a increase and decrease the excitation level of mode Q a by one.…”

“…Several approaches to understanding linear absorbance and emission bandshapes have been presented. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] While most of these studies invoke the Born-Oppenheimer approximation, significant process has also been made to include nonadiabatic effects. [15][16][17][18][19][20] However, due to the large computational demands of accounting for coupling between different electronic states when nonadiabatic effects are important, only the most important vibrational degrees of freedom were included in the quantum representation of the system while the remaining normal modes were represented as a harmonic bath.…”

Incoherent broad-band cavity-enhanced absorption spectroscopy

“…Azulene possesses 17 totally symmetric a 1 modes, 16 in-plane modes of b 1 symmetry as well as 9 b 2 and 6 a 2 out-of-plane modes [Negri93]. Each possible combination of an arbitrary number of fundamental modes potentially contributes to the density of eigenstates [Haarhoff63] in the singlet manifold and hence to the line density in the observed spectrum.…”

S2−S0 Spectroscopy of the van der Waals Complexes of Azulene with Rare Gases

“…11 In particular, we agree on the wavenumber of the origin, the wavenumbers of strong bands in the S 2 -S 0 excitation and emission spectra, and most of the vibrational assignments. However, an examination of important additional details which can be observed in our S 2 -S 0 spectra led us to discover some inconsistencies and errors in band assignments made in previous studies [10][11][12][13][14][16][17][18][27][28][29][30][31][32][33][34][35][36][37] of the spectroscopy and dynamics of azulene. None of these assignments involve bands which are crucial to the interpretation of the spectra of azulene's van der Waals complexes in the present work.…”