Open AccessOne- and two-photon absorption properties of quadrupolar thiophene-based dyes with acceptors of varying strengths
Author(s) -
Sofía Canola,
Lorenzo Mardegan,
Giacomo Bergamini,
M. Villa,
Angela Acocella,
Mattia Zangoli,
Luca Ravotto,
Sergei A. Vinogradov,
Francesca Di Maria,
Paola Ceroni,
Fabrizia Negri
Publication year - 2019
Publication title -
photochemical and photobiological sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.699
H-Index - 101
eISSN - 1474-9092
pISSN - 1474-905X
DOI - 10.1039/c9pp00006b
Subject(s) - density functional theory , acceptor , two photon absorption , polarizability , polarizable continuum model , absorption (acoustics) , chromophore , thiophene , molecular physics , chemistry , absorption spectroscopy , computational chemistry , materials science , atomic physics , photochemistry , physics , molecule , quantum mechanics , organic chemistry , solvation , laser , composite material
The one-photon (1P) and two-photon (2P) absorption properties of three quadrupolar dyes, featuring thiophene as a donor and acceptors of varying strengths, are determined by a combination of experimental and computational methods employing the density functional theory (DFT). The emission shifts in different solvents are well reproduced by time-dependent DFT calculations with the linear response and state specific approaches in the framework of the polarizable continuum model. The calculations show that the energies of both 1P- and 2P-active states decrease with an increase of the strength of the acceptor. The 2P absorption cross-sections predicted by the response theory are accounted for by considering just one intermediate state (S 1 ) in the sum-over-states formulation. For the chromophore featuring the stronger acceptor, the energetic positions of the 1P- and 2P-active states prevent the exploitation of the theoretically predicted very high 2P activity due to the competing 1P absorption into the S 1 state.