Zhou Yong-Hong, Wang Na-Li, Miao Ti-Fang, Wang Juan-Gang, Wang Zhe-Yu
School of Chemistry and Material Science, Huaibei Normal University, Huaibei, 235000, People's Republic of China,
J Fluoresc. 2015 Mar;25(2):473-9. doi: 10.1007/s10895-015-1547-8. Epub 2015 Mar 3.
Two novel metal complexes, namely [Tb2(L)6(H2O)4]·(NO3)6·L2·(H2O)18 (1) and [Hg(L)Cl2]n (2), were obtained by the reaction of D-π-A (D = donor, π = conjugated spacer, A = acceptor) type pyridinium inner salt dye, trans-4-[(p-N,N-dimethylamino)styryl]-N-(2-propanoic-acid) pyridinium (L) with corresponding metal salts. Single crystal X-ray diffraction analyses reveal that compound 1 possesses dinuclear motif in which two Tb(III) ions are linked by four carboxylate groups while complex 2 exhibits 1D chain structure based on Hg(II) ions bridged by carboxylate groups. The linear and non-linear optical properties of complexes 1 and 2 have been studied. Both 1 and 2 exhibit intense single-photon excited fluorescence (SPEF) and two-photon excited fluorescence (TPEF) in the red range. Results show that the replacement of central ions from Hg(2+) to Tb(3+) influence the two-photon absorption cross-section significantly through increasing the density of the chromophore. However, the peak positions of two-photon excited fluorescence are only slightly affected. Compared with L molecule, complex 1 shows enhanced two-photon absorption cross-section and decreased fluorescent lifetime.
通过D-π-A（D =给体，π =共轭间隔基，A =受体）型吡啶内盐染料反式-4-[(对-N，N-二甲基氨基)苯乙烯基]-N-(2-丙酸)吡啶鎓（L）与相应金属盐反应，得到了两种新型金属配合物，即[Tb2(L)6(H2O)4]·(NO3)6·L2·(H2O)18（1）和[Hg(L)Cl2]n（2）。单晶X射线衍射分析表明，化合物1具有双核结构，其中两个Tb(III)离子通过四个羧酸根基团相连，而配合物2呈现基于由羧酸根基团桥连的Hg(II)离子的一维链状结构。对配合物1和2的线性和非线性光学性质进行了研究。1和2在红色范围内均表现出强烈的单光子激发荧光（SPEF）和双光子激发荧光（TPEF）。结果表明，中心离子从Hg(2+)替换为Tb(3+)通过增加发色团密度显著影响双光子吸收截面。然而，双光子激发荧光的峰值位置仅受到轻微影响。与L分子相比，配合物1表现出增强的双光子吸收截面和缩短的荧光寿命。
