Multifunctional magnetic materials obtained by insertion of spin-crossover Fe~(III) complexes into chiral 3D bimetallic oxalate-based ferromagnets

摘要

The syntheses, structures, and magnetic properties of compounds of formula [Fe~(III)(5-Clsal_2-trien)][Mn~(II)Cr ~(III)(ox)_3]?0.5(CH_3NO_2) (1), [Fe~(III)(5-Brsal_2-trien)][Mn~(II)Cr ~(III)(ox)_3] (2), and [In~(III)(5-Clsal _2-trien)][Mn~(II)Cr~(III)(ox)_3] (3) are reported. The structure of the three compounds, which crystallize in the orthorhombic P2_12_12_1 chiral space group, presents a 3D chiral anionic network formed by Mn~(II) and Cr ~(III) ions linked through oxalate ligands with inserted [Fe ~(III)(5-Clsal_2-trien)]~+, [Fe~(III)(5- Brsal_2-trien)]~+, and [In~(III)(5-Clsal _2-trien)]~+ cations. The magnetic properties indicate that the three compounds undergo long-range ferromagnetic ordering at ca. 5 K. On the other hand, the inserted Fe~(III) cations undergo a partial spin crossover in the case of 1 and 2.