title: Theoretical study of two-photon absorption properties of a series of ferrocene-based chromophores.
abstract: The electronic structures, one-photon absorption (OPA), and two-photon absorption (TPA) properties of a series of ferrocene-based chromophores with TCF-type acceptors (TCF = 2-dicyanomethylene-3-cyano-4-methyl-2,5-dihydrofuran) have been studied by using the ZINDO-SOS method. The results have revealed that OPA and TPA of ferrocenyl derivatives are affected by the strength of the acceptor, especially the pi-bridge conjugation length. The TPA cross section increases with increasing acceptor strength and pi-bridge conjugation length. The TCF-type acceptor with a phenyl group can lead to a larger TPA cross section. Quadrupole molecules have the largest TPA cross sections (2000-3000 GM), which are about 4 times that of the corresponding dipolar molecules, indicating larger interactions between the top and bottom branches. Finally, the origins of the two-photon excitations for ferrocenyl derivatives are analyzed. The calculations show that ferrocenyl derivatives with TCF-type acceptors (especially quadrupole molecules) are promising candidates for TPA materials.
authors.affiliation: State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Changchun, 130023, China.
authors.forename: Xiang-Biao
authors.initials: XB
authors.lastname: Zhang
authors.forename: Ji-Kang
authors.initials: JK
authors.lastname: Feng
authors.forename: Ai-Min
authors.initials: AM
authors.lastname: Ren
authors.forename: Chia-Chung
authors.initials: CC
authors.lastname: Sun