Tuning the Ising-type anisotropy in trigonal bipyramidal Co(ii) complexes

Abstract

This paper demonstrates the engineering and tuning of Ising-type magnetic anisotropy in trigonal bipyramidal Co(II) complexes. Here, we predict that employing a ligand that forces a trigonal bipyramidal arrangement and has weak equatorial σ-donating atoms, increases (in absolute value) the negative zero field splitting parameter D. With these considerations in mind, we used a sulfur containing ligand (NS₃^iPr), which imposes a trigonal bipyramidal geometry to the central Co(II) ion with long equatorial Co–S bonds. The resulting complex exhibits a larger anisotropy barrier and a longer relaxation time in comparison to the complex prepared with a nitrogen containing ligand (Me₆tren).