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Pb(NO_3)_2与3-氟邻苯二甲酸(H2Fpht)和2,2′-联吡啶(bpy)在不同水热反应温度下获得了2个新的配位聚合物:[Pb(Fba)(bpy)(NO_3)]_n(1)和[Pb_4O_2(Fba)_4]_n(2)。3-氟邻苯二甲酸配体经由原位脱羧生成了3-氟苯甲酸根(Fba)。配合物1具有Pb-NO_3-Pb双螺旋链结构,是由硝酸根桥联四方反棱柱[PbO_6N_2]结构单元而形成,而Fba与bpy配体螯合配位于中心铅离子。配合物2为PbOH-Pb链状结构,包含四面体结构单元[Pb_4(μ4-OH)_4]~(4+),且具有4个晶体学独立的铅离子中心:Pb(1)O_6、Pb(2)O_6、Pb(3)O_5和Pb(4)O_5。这两个配合物链分别经氢键作用力自组装为三维超分子网络结构。室温下,测定了配合物的固体荧光光谱,均显示为基于配体的荧光发射。有意思的是,通过荧光淬灭机理配合物2可以选择性地检测硝基苯。
Two novel coordination polymers of Pb (NO_3) _2 with 3-fluorophthalic acid (H2Fpht) and 2,2’-dipyridyl (bpy) were obtained at different hydrothermal reaction temperatures: (bpy) (NO_3)] _ n (1) and [Pb_4O_2 (Fba) _4] _n (2). 3-Fluorobenzoate (Fba) was generated by in situ decarboxylation of 3-fluorophthalic acid ligands. Complex 1 has a Pb-NO_3-Pb double-helical chain structure formed by nitrate bridged tetragonal antipolyposite [PbO_6N_2] structural units, whereas Fba and bpy ligands chelate with central lead ions. Complex 2 is a PbOH-Pb chain structure containing tetrahedron [Pb_4 (μ4-OH) _4] ~ (4+) and has four crystallographic centers of Pb ions: Pb (1) O_6, Pb (2) O_6, Pb (3) O_5 and Pb (4) O_5. The two complex chains are self-assembled into three-dimensional supramolecular network structure by hydrogen bonding forces respectively. The solid fluorescence spectra of the complexes were determined at room temperature, all of which showed ligand-based fluorescence emission. Interestingly, nitrobenzene can be selectively detected by the fluorescence quenching mechanism of complex 2.