One new organic-inorganic hybrid supramolecular complex TAPC [(TAP-NH3 )·(18-crown-6)·0.5 (H2 O)]·2 (ClO-4 )with electrical bistability has been successfully obtained by the reaction of 4-amino-2,2,6,6-tetramethylpiperidine (TAP-NH3 ),HClO4 and 18-crown-6.The complex was characterized by element analysis,variable-temperature X-ray single-crystal diffraction analysis,TG,DSC,powder XRD and temperature-dependent dielectric measurement.X-ray single-crystal analysis re-veals that complex 1 (TAPC)belongs to monoclinic system,space group P21/m at both room and high temperature.Complex 1 is a switchable dielectric material with electrical bistability.The-NH+3 nests in the 18-crown-6 ring to form a supramolecular ro-tator-stator-like structure.The order-disorder transition of the ClO-4 anions and the relative displacement of the guest molecule H2 O are not only the significant difference in structures at different temperatures,but also the two main factors contributing to this reversible first-order phase transition at high temperature.This result has also been verified by a pair of strong peaks in the DSC measurement and a large thermal hysteresis at 37.2 K.%将4-氨基-2，2，6，6-四甲基哌啶、高氯酸和18-冠-6以一定配比反应，成功地合成了一种新型的具有电学双稳态特性的有机-无机杂化的超分子基化合物 TAPC，TAPC＝[（TAP-NH3）·（18-crown-6）·0．5（H2 O）]·2（ClO－4），并通过元素分析、变温X 射线单晶结构测定、热重分析、差式扫描量热法、X 射线粉末衍射及变温介电测量对其进行表征。单晶结构解析表明，该化合物在室温和高温下均属于单斜晶系，P21／m 空间群。化合物1（TAPC）是具有电学双稳态特性的可转换的介电材料，－NH+3嵌入18-冠-6的分子大环内，形成一种超分子转子-定子式的结构。ClO－4离子的有序-无序相变和客体水分子的位移效应不仅是不同温度下晶体结构之间的显著区别，而且是化合物 TAPC 在高温下发生明显的一级可逆相变的主导因素。DSC 测量中的一对尖峰和37．2 K 时的强热滞现象也证实了这一结果。
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