The Dielectric Properties Of Organic Phosphate And Crown Ether Compounds

Phase materials have attracted increasing attentions in recent years, due to their potential applications in the information storage, optical sensing, and piezoelectric sensors. Crown ether, as a neutral ligand, is able to the alkali metals, alkaline earth metals, ammonia and derivatives complexed to form stable complexes. In order to find new phase materials, we have designed and synthesized a series of crown ether inclusion compounds and metal complexes with nitrogen-containing crown ethers of trimethyl phosphine derivatives, cultivate single crystals, and the structures and referral studied electrical nature of the phase transition-related features.This thesis consists of 11 crystalline structures: (C12H24O6)·(C5H16PN)2+·CdBr42- (1), (C12H24O6)·(C5H16PN)2+·MnCl42-(2), (C12H24O6)·(C5H16PN)2+·2PF6- (3), (C12H24O6)·K+·CrO3Cl- (4), (C12H24O6)·K+·CrO3Br-(5), (C12H24O6)·Rb+·CrO3Cl- (6), (C12H24O6)·Rb+·CrO3Br- (7), (C12H24O6)·Ba2+·Cr2O72- (8), (C12H24O6)(H2O)·Ba2+·Cr2O72-(9), (C10H20O5)2·Cs+·CrO3Cl- (10) and (C10H20O5)2·Cs+·CrO3Br-(11). We respectively measured the infrared (IR), powder diffiction (PXRD), crystal structure and the dielectric properties of these eleven kinds of compounds. Experimental results show that the crystal 3,10 and 11 were observed dielectric anomalies, which these reveal that the phase transitions may occur. Crystal 3 is confirmed the reversible isostructural phase transition, which undergoes a reversible phase transition at around 295 K. The rotation or motion of 18 crown 6 and the order-disorder transformations of PF6- anions in compound 3 are related to the phase transition. Crystals 10 and 11 have undergone two successive phase transitions, the temperature of phase transitions are different, due to the different anions. Several other compounds in the heating and cooling process show no dielectric anomalies.