Zhang Y, Guo J, Li X, Zhao M, Wei Q, Song P. One- and two-photon absorption properties of quadrupolar A-π-D-π-A dyes with donors of varying strengths.
SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020;
230:118015. [PMID:
31978692 DOI:
10.1016/j.saa.2019.118015]
[Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 12/12/2019] [Accepted: 12/27/2019] [Indexed: 06/10/2023]
Abstract
In this work, the one- and two-photon absorption properties of two quadrupolar A-π-D-π-A dyes, featuring carbazole and triphenylamine as donors of varying strengths, are calculated using density functional theory. The characteristics of two-photon excitation are analysed by using the three-state model closest to the real physical process. By taking the intermediate state as a bridge, the charge transfer characteristics in the two-photon excitation process are studied in detail by using various visualisation methods. Comparing the intramolecular charge transfer (ICT) characteristics shows that increasing the ability of the push-pull electrons of the central substituents, thus increasing the intramolecular charge transfer, is a more efficient method to enhance the molecular σtp. Our study promotes a deeper understanding of the design of A-π-D-π-A molecules with large cross-sections in two-photon absorption.
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