The Organicinorganic Hybrid Structure And Dielectric Properties Of Quasi-spherical Organic Cations

Organic-inorganic hybrid compounds are attracting more and more attention due to their diversity of organic and inorganic components,which can control their performance.In order to find a controllable multifunctional molecular phase transition material,we synthesized eight new types of organic-inorganic hybrids by adjusting the position of the chiral center in the organic molecules,modifying the organic cations with halogen atom,and adjusting the inorganic components:[2-OH-C₃H₆-N(C₃H₇)₃][Mn(dca)₃](1),[2-OH-1-CH₃-C₂H₃-N(C₃H₇)₃][Mn(dca)₃](2),[(Me)₃CN(Me)₂CH₂F]₂[Cd Br₄](3),[(Me)₃CN(Me)₂CH₂F]₃[Bi₂Cl₉](4),[(Me)₃CN(Me)₂CH₂F]₃[Bi₂Br₉](5),[(Me)₃CN(Me)₃]₂[Bi Rb Br₆](6),[(Me)₃P(CH₂)₂Cl]₂[Bi Rb Br₆](7)and[C₆H₁₁N]₂[Bi Rb Br₆](8)This thesis introduces the physicochemical properties of the eight compounds synthesized,such as the crystal structure,phase transition behavior,and dielectric properties.It is mainly divided into three parts.The first two parts are mainly about the modification of organic molecules,(1)Chapter 3,the study of multifunctional property regulation with ferroelastic phase transition and two-step switching of quadratic NLO signal.By designing the position of the chiral center inside the organic molecule,compound 2 is a multifunctional material with ferroelasticity and NLO switching characteristics,and compound 2 has three phase transitions,and the phase transition temperature is higher than that of compound 1 with only one phase transition.(2)Chapter 4,about the preparation and characterization of the hybrid compounds of N,N-dimethylfluoromethyl tert-butylamine.After synthesizing the fluorine-substituted(Me)₃CN(Me)₂CH₂F·Br organic molecules and hybrids,through DSC,dielectric,crystal structure and other characterization methods,it is found that compound 3 has a phase transition,the phase transition temperature is 259.75 K,and compound 4 has two phase transitions,the phase transition temperature is 200.85 K and 334.55 K.As a system with the same cation,compound 5 has no phase transition.The last part is about the modification of the inorganic metal framework,(3)Chapter 5,the study of the properties of double-perovskite organic-inorganic hybrid compounds.Using Bi and Rb as the framework,the three compounds obtained are all one-dimensional chains.Compound 6 has no phase transition,compound 7 has undergone a phase transition,the phase transition temperature is 295.75 K at room temperature,and compound 8 has undergone a phase transition.The phase transition temperature is 358.85 K.