Study On Synthesis,Phase Transition,Dielectric And Nonlinear Optical Properties Of Quasi-Spherical Amine Organic-Inorganic Hybrid Crystals

Organic-inorganic hybrid phase transition materials have great potential applications in optical devices and energy storage due to their dielectric,nonlinear optical and ferroelectric properties which are triggered by temperature,light,electric field.Therefore,the exploration and synthesis of excellent organic-inorganic hybrid materials become one of the frontier topics.Because the cationic components of small organic amine molecules usually respond to external stimuli and undergo structural phase transition,the research on phase-transition materials has focused on organic small molecule amines.According to the"quasi-spherical theory","momentum matching theory"and"fluorination effect"proposed recently,we have designed and synthesized a series of novel quasi-spherical amine organic molecules,and then synthesized different organic-inorganic hybrid compounds with these amines.The phase transition,dielectric and nonlinear optical properties of the organic-inorganic hybrid compounds were studied.In the first part of this thesis,three novel quasi-spherical amines were designed and prepared,named 2-azabicyclo[2.2.2]octan-3-one(3-O-isoQ),2-methyl-2-azabicyclo[2.2.2]Octane(2-Me-isoQ),and 2-azabicyclo[2.2.2]octane(isoQ).Then,[3-O-isoQH]ReO4(1),[2-Me-isoQH]ReO₄(2),[isoQH]ReO₄(3),[(C₇H₁₄N)(CdCl₃)]₂·H₂O(4)and[C₇H₁₄N]₂[MnCl₄](5),five organic-inorganic hybrid compounds were synthesized.Among them,compounds 2,3,4 and 5 not only undergo structural phase transition driven by temperature,but also have dielectric properties.In addition,compound 3 has reversible nonlinear optical properties.In the second part of the thesis,four organic-inorganic hybrid compounds[C₆H₁₁NF][ReO₄](6),[C₆H₁₁FN]₄[ClO₄]₅H₃O(7),[C₆H₁₁NF]₃[CdCl₃][CdCl₄](8)and[C₆H₁₁NF]₃[MnCl₃][MnCl₄](9)were synthesized using 4-fluoro-1-azabicyclo[2.2.1]heptane as a ligand.Among them,compounds 6 and 7 have structural phase transition and dielectric response,and compounds 8 and 9 have anti-perovskite crystal structures.In the third part of the thesis,1-azabicyclo[3.2.2]nonane and 5-fluoro-1-azabicyclo[3.2.2]nonane were used as ligands to synthesize[C₈H₁₅NF][ReO₄](10),[C₈H₁₅NF][ClO₄](11),[C₈H₁₆N]₂[ZnBr₄](12).Among them,compounds 10 and 12have structural phase transition and dielectric response.In summary,the quasi-spherical organic amines obtained by structural modification of spherical molecules were combined with inorganic acids or metal halides to obtain a variety of organic-inorganic hybrids with structural phase transitions and photoelectric properties.