Anderson型杂多酸-DABCO复合二维相变晶体材料的合成及介电性质

以1.4-二氮杂二环2.2.2]辛烷(DABCO)氟硼酸盐与(NH4)3FeMo6 O24 H6]·7H2 O多酸盐为原料,通过H管水溶液界面扩散方式合成一种新颖的Anderson型超分子化合物(H2 DABCO)2FeMo6 O24 H4]·4H2 O(1).并通过红外光谱、单晶X衍射、元素分析、XRD粉末衍射...

Synthesis and dielectric properties of Anderson-type heteropoly acids-DABCO two-dimensional phase transition crystalline materials

A new Anderson supramolecular compound(H₂DABCO)₂FeMo₆O₂₄H₄]·4H₂O(1)was synthesized by 1.4-diazodicylic2.2.2]octane(DABCO),(NH₄)₃FeMo₆O₂₄H₆]·7H₂O and tetrafluoroboric acid using water as solvent through H-tube interface diffusion method.The structure,thermal stability and electrical properties of supramolecular compounds were characterized by infrared spectroscopy,single crystal X-ray diffraction,elemental analysis,XRD,TG,DSC and dielectric constant testing.The results of single crystal X-ray diffraction prove that the crystal at low temperature belongs the triclinic space group P-1.The polyacid anions and water molecules form a two-dimensional network structure through hydrogen bondings,water molecules move appreciably with the change of temperature.DABCO cation is filled in the two-dimensional layered structure of adjacent poly acid anions with N-H…O hydrogen bondings and significant molecular writhing occurs with temperature.This results in the phase transition and reversible phenomenon of stepped dielectric constant around 233 K and 271 K.