中文摘要：

报道了十字形结构对荧光生色团的双光子吸收（TPA）作用横截面积的影响．1，4-二（9＇-乙基咔唑基）-3＇-乙烯基苯（R1）是经典的具有D-π-D结构的TPA生色团．通过一个联苯桥将两个双光吸引（TPA）链连接在一起得到的十字形分子（1）显示出比单链分子明显增大的双光子吸收作用横截面积（σ’）．在10^-4mol／L的甲苯溶液中，十字结构分子1的σ’值为491．0×10^-50cm^4·s，而R1的σ’值仅为137．5×10^-50cm^4·s．σ’的放大可以归结为十字结构使TPA生色团的偶极呈交叉排列，抑制了浓溶液中的荧光猝灭．

英文摘要：

The effect of cruciform structure on the two photon absorption action cross-section of fluorescence chromophore was reported. 1,4-Di（9＇-ethyl-carbazolyl）-3＇-vinylbenzene （R1） is a classic two photon absorp- tion（TPA） chromophore with D-π-D structure. By linking two TPA chains with a biphenyl bridge, the ob- tained cruciform molecule （1） exhibits evidently larger two photon absorption action cross-section （σ＇） than its single-chain counterpart. For example, in 10^-4 mol/L toluene solution, cruciform 1 shows a σ＇ value of 491.0 × 10^-50 cm^4 ·s, while the σ＇ value of R1 is only 137.5 × 10^-50 cm^4 ·s. The amplification of σ＇ was ascribed to the cruciform structure, which rendered the TPA chromophores with cross dipole arrangement and curbed the fluorescence quenching in concentrated solutions.