Multiresponsive Spin Crossover Driven by Rotation of Tetraphenylborate Anion in an Iron(Ⅲ)Complex  

作　　者：Si-GuoWu Md.Najbul Hoque Jie-Yu Zheng Guo-Zhang Huang Nguyen Vu Ha Anh Liviu Ungur Wei-Xiong Zhang Zhao-Ping Ni Ming-Liang Tong 

机构地区：[1]Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education,School of Chemistry,Sun Yat-Sen University,Guangzhou 510275 [2]Department of Chemistry,National University of Singapore,Singapore 117543

出　　处：《CCS Chemistry》2021年第1期453-459,共7页中国化学会会刊（英文）

基　　金：supported by the National Key Research and Development Program of China(2018YFA0306001);the NSFC(21773316,21771200,and 21821003);the Pearl River Talent Plan of Guangdong(2017BT01C161);The scientific grants R-143-000-A80-114 and R-143-000-A65-133 from;National University of Singapore are gratefully acknowledged.Computational resources from NSCC(ASPIRE-1,grant no.11001278)were used for this study.

摘　　要：Dynamic molecular materials,which involvemechanical motions in crystals,usually exhibit tunable properties related to conformational polymorphs.Herein,we describe a solvent-free molecular crystal[{FeⅢ(salten)}2(TPB)](BPh_(4))_(2)(Ⅰ)developed by associating the rotatable tetraphenylborate anion with the spin crossover(SCO)binuclear iron(Ⅲ)cation.The solvent-free phaseⅠcan undergo a temperature-induced phase transformation to phaseⅡ,during which rotation of the BPh4−anion interplays with the SCO component,giving rise to fascinating variations in SCO(from gradual to abrupt)and dielectric properties.Most importantly,an unexpected polymorphic transformation fromⅡtoⅢorⅣ,with increasing magnetic hysteresis,is realized by exposingⅡto water or ethanol vapor;the transition is reversible by heating.This rare successive transformation is further rationalized by theoretical calculations.Hence,this multiresponse system provides a new way for modulating synergistic effects and designing dynamic SCO materials by integrating intramolecular motions in the crtystal lattice.

关 键 词：INTRAMOLECULAR motion iron(Ⅲ) spin crossover POLYMORPH single-crystal-to-singlecrystal transformation 

分 类 号：O62[理学—有机化学]