Bis-methyl imidazolium methylidene bis(trifluoromethanesulfonyl)imide, crystal structure, thermal and dielectric studies

Abstract

A new geminal di-cationic ionic liquid (IL) containing a central cationic unit methylidene capped by a basic functionality (imidazole) is synthesized. The compound was characterized by means of 1H, 13C, 19F NMR, IR and Raman spectroscopies and its crystal structure is confirmed by single crystal X-ray diffraction method. The X-ray studies on ([M(CH2)IM2+][2NTf-2]) show that it crystallizes in monoclinic system with space group: P 21/c. Thermal properties were investigated in the temperature range from 0 to 400.C by using differential thermal (DTA) and thermogravimetric (TGA) analyses. The frequency-dependent electrical data are discussed using complex dielectric permittivity in the frequency range of (10-2-106 Hz) and in the temperature range of -50. to 20°C. The outstanding dielectric and thermal properties make this IL as promising candidate for electrochemical devices.