High temperature spin crossover behaviour of mononuclear bis-(thiocyanato)iron(ii) complexes with judiciously designed bidentate N-donor Schiff bases with varying substituents

Abstract

We present herein the solvent and substituent dependent diverse spin crossover behaviours of molecular bis-(thiocyanato)iron(ii) complexes with smartly designed bidentate Schiff bases above room temperature.

Chiral spin-crossover complexes based on an enantiopure Schiff base ligand with three chiral carbon centers

“… 7 A similar trend has been observed in other bis-(thiocyanato) Fe( ii ) complexes of [4-X- N -(phenyl(pyridin-2-yl)methylene)aniline] (X = Cl, Br, CH 3 ). 12 …”

“…Fe(II) complexes. 7,12 In contrast to [Fe(RR-or SS-L 3 )(NCSe) 2 ] compounds irradiation with 808 nm induced an increase of the signal instead of the reverse-LIESST effect observed for those compounds. 7…”

“…The T (LIESST), defined as the minimum of the derivative of χ M T after irradiation with temperature, is 70 K for [Fe(RR-Sor SS-R-L 2 )(NCS) 2 ] and 50 K for [Fe(RR-S-or SS-R-L 2 )(NCSe) 2 ] in line with that obtained for other bis-(thiocyanato) or bis-(selenocyanato) Fe(II) complexes. 7,12 In contrast to [Fe(RR-or SS-L 3 ) (NCSe) 2 ] compounds irradiation with 808 nm induced an increase of the signal instead of the reverse-LIESST effect observed for those compounds. 7…”