A series of compounds [Fe II H 3 L Me ]Br·Y·nMeOH (Y=PF6- (1), AsF6- (2), SbF6- (3), CF3SO3- (4); n=0 or 1) were synthesized, where H 3 L Me is a hexadentate N 6 tripodal ligand of the neutral form, tris[2-(((2-methylimidazol-4-yl)methylidene)amino)ethyl]amine, and their structures and magnetic properties were investigated. The compounds 1−3 with counter anions Y=PF6-, AsF6-, and SbF6- contain methanol as a crystal solvent, and show no SCO behaviors, while the corresponding Cl − compounds have no crystal solvent and show a variety of SCO behaviors. The compound [Fe II H 3 L Me ]Br·CF 3 SO 3 (4) has no crystal solvent and has isomorphous structure to the Cl − compounds, and shows an abrupt spin transition between the HS (S=2) and LS (S=0) states with a hysteresis about 2K and large frozen-in effect below 72K. The T 1/2↑ and T 1/2↓ values are 98 and 96K, whose values are higher than those of corresponding Cl − compound about 15K and the width of hysteresis is narrower than that of corresponding Cl − compound about 2K. The crystal structures of 4 were determined at 296 and 93K, where the crystal system and space group showed no change between these temperatures. The structures at both temperatures have a same 2D layered structure, which is composed of NH⋯Br − hydrogen bonds between the Br − ion and the imidazole NH groups of three neighboring cations [Fe II H 3 L Me ] 2+ . This network structure is the same as that of corresponding Cl − compound. The 600nm light irradiation at 5K induced the LIESST effect.