High‐Tc Enantiomeric Ferroelectrics Based on Homochiral Dabco‐derivatives (Dabco=1, 4‐Diazabicyclo[2.2.2]octane). (11th August 2020)

• Record Type: Journal Article
• Authors: Fu, Da‐Wei; Gao, Ji‐Xing; He, Wen‐Hui; Huang, Xue‐Qin; Liu, Yu‐Hua; Ai, Yong
• Is Part Of: Angewandte Chemie. Volume 132:Number 40(2020)
• Page Start: 17630
• Page End: 17634
• Publication Date: 2020-08-11
• Subjects: chirality -- ferroelectric domains -- molecular ferroelectrics -- phase transitions -- polarization switching; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202007660
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: 1, 4‐Diazabicyclo[2.2.2]octane (dabco) and its derivatives have been extensively utilized as building units of excellent molecular ferroelectrics for decades. However, the homochiral dabco‐based ferroelectric remains a blank. Herein, by adding a methyl (Me) group accompanied by the introduction of homochirality to the [H2 dabco] 2+ in the non‐ferroelectric [H2 dabco][TFSA]2 (TFSA=bis(trifluoromethylsulfonyl)ammonium), we successfully designed enantiomeric ferroelectrics [ R and S ‐2‐Me‐H2 dabco][TFSA]2 . The two enantiomers show two sequential phase transitions with transition temperature ( T c ) as high as 405.8 K and 415.8 K, which is outstanding in both dabco‐based ferroelectrics and homochiral ferroelectrics. To our knowledge, [ R and S ‐2‐Me‐H2 dabco][TFSA]2 are the first examples of dabco‐based homochiral ferroelectrics. This finding opens an avenue to construct dabco‐based homochiral ferroelectrics and will inspire the exploration of more eminent enantiomeric molecular ferroelectrics. Abstract : The first examples of homochiral dabco‐based (dabco=1, 4‐diazabicyclo[2.2.2]octane) ferroelectrics, [ R ‐ and S ‐2‐Me‐H2 dabco][TFSA]2 (TFSA=bis(trifluoromethylsulfonyl)ammonium), were designed from the non‐ferroelectric [H2 dabco][TFSA]2 . They show two phase transitions with a transition temperature ( T c ) up to 405.8 K and 415.8 K, higher than the T c of most dabco‐based or homochiral ferroelectrics.