Synthesis and Electro-optical Properties of a Novel Nonlinear Optical Chromophore Containing 4, 4-dihexyl-4H-cyclopenta [2,1-b:3,4-b'] dithiophene as π Bridge

doi:10.7517/j.issn.1674-0475.2015.04.300

Abstract

Abstract:

A novel second-order nonlinear optical chromophores containing 4, 4-dihexyl-4H-cyclopenta[2,1-b:3,4-b']dithiophene (CPDT) as π-electron bridges was prepared, and its chemical and physical properties were systematically evaluated. UV-Vis spectra, thermal stability and density functional thoery (DFT) calculations revealed that CPDT as π-spacer can dramatically enhance intramolecular charge transfer (ICT) properties and narrow the energy gaps. And due to the hindrance of dihexyl, the chromophore showed weak dipole-dipole aggregation. As expected, the poled polymer film which was prepared by doping chromophore A into amorphous polycarbonate(APC) with 20%(mass fraction) doping density, exhibited 85 pm/V in electro-optical (EO) coefficient test.

Key words: nonlinear opticalmaterial, chromophore, eocoefficient, hyperpolarizability

YANG Dan, XU Huajun, CONG Shengyu, BO Shuhui, QIU Ling, ZHEN Zhen, LIU Xinhou. Synthesis and Electro-optical Properties of a Novel Nonlinear Optical Chromophore Containing 4, 4-dihexyl-4H-cyclopenta [2,1-b:3,4-b'] dithiophene as π Bridge[J]. Imaging Science and Photochemistry, 2015, 33(4): 300-306.

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