1,4‑二氮杂二环[2.2.2]辛烷衍生物的卤代作用有效诱导介电相变  

Dielectric Phase Transition Induced by Halogen Substitution Based on 1,4‑Diazabicyclo[2.2.2]octane‑Derivatives

作　　者：程赛楠 丁坤 宋泷藤 张铁[1] 张志旭 张毅[1] 付大伟[1] CHENG Sai‑Nan;DING Kun;SONG Shuang‑Teng;ZHANG Tie;ZHANG Zhi‑Xu;ZHANG Yi;FU Da‑Wei(Ordered Matter Science Research Center,Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics,Southeast University,Nanjing 211189,China)

机构地区：[1]东南大学,分子铁电科学与应用江苏省重点实验室,有序物质科学研究中心,南京211189

出　　处：《无机化学学报》2021年第6期961-967,共7页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.21991141)资助。

摘　　要：我们通过精确的分子设计,得到3种1,4‑二氮杂二环[2.2.2]辛烷(Dabco)衍生物X‑EtHDabco(EtDabco=N‑乙基‑1,4‑二氮杂双环[2.2.2]辛烷,X=H、F、Cl)。分别以3种Dabco衍生物、溴化锌为原料按一定配比反应,成功地合成了一系列新型有机-无机杂化相变材料(H‑EtHDabco)[ZnBr_(4)](1)、(F‑EtHDabco)[ZnBr_(4)](2)、(Cl‑EtHDabco)[ZnBr_(4)](3)。变温X射线单晶结构测定、差式扫描量热法(DSC)及介电测量结果表明:没有卤素取代的1在测试温度范围内并未观察到任何相变,然而卤素取代的化合物2和3均在230 K附近触发了可逆同结构相变。2和3产生的相变是有机胺阳离子中的卤素取代基在室温相和低温相中的有序-无序转变和无机骨架的相对变形共同引起的。We successfully synthesized(X‑EtHDabco)[ZnBr_(4)](X=H,F,Cl for compound 1,2,and 3,EtDabco=Nethyl‑1,4‑diazoniabicyclo[2.2.2]octane)through precise molecular design.Systematic measurements(powder X‑ray diffraction,differential scanning calorimetry measurements,dielectric measurements)were performed on these compounds.It is noteworthy that,no hint of heat anomaly was observed for 1,while both 2 and 3 displayed intriguing isostructural order‑disorder phase transition near 230 K.Through the analysis of the crystal structure,the orderdisorder transformation of organic ammonium plays a major role in the phase transition,in addition,the displacement of the inorganic framework also contributes to dielectric response.CCDC:2032032,1(293 K);2032034,2(213 K);2032033,2(293 K);2031906,3(298 K);2032037,3(202 K).

关 键 词：卤素取代 有机-无机杂化 可逆相变 介电性质 单晶 

分 类 号：O614.241[理学—无机化学]