A three-dimensional (3D) Cd-CP [Cd(H₂L)]_n was synthesized under hydrothermal conditions [H4L=1H,1′H-[2,4′-biimidazole]-4,5-dicarboxylicacid]. The structure of [Cd(H₂L)]_n was characterized by single-crystal X-ray diffraction and the result shows that it exhibits a non-centrosymmetric lig(LiGe) network constructed from interconnecting C₂-symmetric metallacalix[4]arenes Cd₄(H₂L)₄ MBBs. This complex exhibits light blue fluorescence emission originated from intraligand π∗→π electron transition, indicating that the d10 metal ions can hardly absorb energy and thus have no interference with the fluorescence of the ligand. The UV–Vis was used to investigate the optical property of the sample, which is essentially not absorbed in the visible light area and the band gap of the sample is about 2.2eV. Moreover, nonlinear optical (NLO) determination shows that the sample exhibits an obvious second-harmonic generation (SHG) response of ∼1.2×urea.

中文翻译：

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基于金属杯[4]芳烃分子构件的3D配位聚合物的生长和SHG

三维 (3D) Cd-CP [Cd(H ₂ L)]_n在水热条件下合成[H4大号=1H,1'H-[2,4'-联咪唑]-4,5-二羧酸]。[Cd(H ₂ L)]的结构_n通过单晶X射线衍射对其进行了表征，结果表明它表现出由相互连接的C ₂ -对称金属杯[4]芳烃Cd ₄ (H ₂ L) ₄ MBBs构成的非中心对称lig(LiGe)网络。该复合物表现出源自内配体的浅蓝色荧光发射π*→π电子跃迁，表明 d10金属离子几乎不能吸收能量，因此对配体的荧光没有干扰。UV-Vis 用于研究样品的光学性质，在可见光区域基本不被吸收，样品的带隙约为 2.2eV。此外，非线性光学 (NLO) 测定表明，样品表现出明显的二次谐波产生 (SHG) 响应～1.2×尿素.