Koynov Kaloian, Bahtiar Ayi, Bubeck Christoph, Mühling Bastian, Meier Herbert
Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany. koynov@ mpip-mainz.mpg.de
J Phys Chem B. 2005 May 26;109(20):10184-8. doi: 10.1021/jp0508913.
Third-harmonic generation (THG) spectroscopy was performed for oligo(1,4-phenyleneethynylene)s (OPEs) with terminal donor-acceptor (DA) substitution and compared to the results of merely donor substituted OPEs and regular OPE chains with 2,5-dipropoxy benzene rings. Both, extension of the conjugation and push-pull effect enhance the molecular hyperpolarizability gamma, even for the DAOPEs, which exhibit a hypsochromic shift of the long-wavelength absorption for increasing length L of the conjugated chain.
对具有末端供体-受体(DA)取代的聚(1,4-亚苯基亚乙炔基)(OPEs)进行了三次谐波产生(THG)光谱分析,并与仅具有供体取代的OPEs以及带有2,5-二丙氧基苯环的常规OPE链的结果进行了比较。共轭的延长和推挽效应均增强了分子超极化率γ,即使对于DA-OPEs也是如此,DA-OPEs随着共轭链长度L的增加,其长波长吸收呈现蓝移。