Ion-pair complexes of Schiff base Fe(iii) cations and complex anions

Abstract

We report on the crystal structure and magnetic properties of four new ion-pair complexes.

Multi‐Magnetic Properties of a Novel SCO [Fe(3‐OMe‐Sal2trien)][Fe(tdas)2]·CH3CN Salt

“…The g 1 -parameter was fixed at 2.00. [4,21,33,34] Moreover, -parameter was also fixed at 370 cm -1 (532.4 K) according to Ewald's value for Fe(S 2 CNR 2 ) 3 complexes. [33] The N-parameter was set equal to 10 since this value is appropriate for most of iron(III) complexes.…”

“…Spontaneous assembly of molecules exhibiting magnetic properties into non-covalently linked stable aggregates, is a promising approach to obtain multi-magnetic "smart" materials, of current interest for application in electronic devices. [1][2][3][4][5][6][7][8][9] In this context, spin-crossover (SCO) Fe(II/III) coordination complexes exhibiting disordering of ethylene (-CH 2 -CH 2 -) groups between two conformers with a narrow thermal hysteresis of 6 K. The dc magnetization measurements and 57 Fe Mössbauer spectroscopy at room temperature are in excellent agreement between γ HS (%) value and ratio of disordering of ethylene groups obtained from X-ray analysis. Mössbauer spectra at 80 K and 296 K indicate a spin transition between S = 1/2 and S = 5/2 for the iron(III) saltrien-cation and confirms S = 3/2 for the [Fe III (tdas) 2 ]anion.…”

“…Spontaneous assembly of molecules exhibiting magnetic properties into non‐covalently linked stable aggregates, is a promising approach to obtain multi‐magnetic “smart” materials, of current interest for application in electronic devices. [ 1–9 ] In this context, spin‐crossover (SCO) Fe(II/III) coordination complexes carrying of magnetic “bi‐stability” at the molecular level, represent one of the promising building blocks for such materials. In these aggregates switching between the low‐spin (LS) and high‐spin (HS) states, induced by variation of temperature and/or pressure and by light irradiation, leads to distinctive changes in magnetism, colour and structure.…”