Field-induced mononuclear cobalt(ii) single-molecule magnet (SMM) based on a benzothiadiazole-ortho-vanillin ligand

Abstract

A unique π-conjugated benzothiadiazole-ortho-vanillin ligand (HL), characterized by single crystal X-ray diffraction and DFT calculations, has been prepared by condensation between 4-amino-benzothiadiazole (BTD) and ortho-vanillin. Its reaction with cobalt(II) acetate...

Chalcogen-bonded donor–acceptor complexes of 5,6-dicyano[1,2,5]selenadiazolo[3,4-b]pyrazine with halide ions

“…in complexes with transition metals, due to the lone pairs of nitrogen atoms. [15][16][17][18][19][20] Besides, they possess chalcogen-centered s-holes [21][22][23][24][25][26] capable of secondary bonding interactions (SBIs) 27 /chalcogen bonding (ChB), i.e. are able to act as s-acceptors.…”

Trinuclear Cobalt(II) Triple Helicate with a Multidentate Bithiazolebis(oxamate) Ligand as a Supramolecular Nanomagnet

“…Successful simulations of the χ M T curve for 1 can only be achieved if both the intramolecular antiferromagnetic interaction and the axial ZFS are taken into account during the fitting process through a spin Hamiltonian for a linear trinuclear model (eq ): In this equation, J and D are the magnetic coupling and axial ZFS and g is a common Zeeman factor for the three Co II ions. Using of a ZFS approach instead of an effective spin one simulating a first-order spin–orbit coupling is justified by the highly distorted coordination spheres at the Co II sites in 1 . , The best-fit parameters are g = 2.61, D = +90.6 cm –1 , and J = −1.80 cm –1 or, alternatively, g = 2.61, D = −88.8 cm –1 , and J = −0.92 cm –1 . In the former case, the theoretical curve better matches the experimental data.…”

“…Using of a ZFS approach instead of an effective spin one simulating a first-order spin−orbit coupling is justified by the highly distorted coordination spheres at the Co II sites in 1. 38,39 The best-fit parameters are g = 2.61, D = +90.6 cm −1 , and J = −1.80 cm −1 or, alternatively, g = 2.61, D = −88.8 cm −1 , and J = −0.92 cm −1 . In the former case, the theoretical curve better matches the experimental data.…”

Zinc(II) and copper(II) complexes with benzothiadiazole Schiff-base ligands

“…Synthesis of 4-amino-2,1,3-benzothiadiazole and ligand HL 2 were performed according to the previously reported procedure (Fig. S1 for the 1 H NMR spectra in DMSO-d 6 ) [26].…”

“…The proximity of the thiadiazole and ortho-vanillin units in this new ligand creates a favourable environment for a tris-chelation involving the adjacent BTD nitrogen atom. We have shown that its neutral cobalt(II) complex of formula [Co(L 2 )2]•CH2Cl2, where the two deprotonated monoanionic ligands chelate the metal centre within a NNO tridentate mode, behaves as a field-induced single-molecule magnet (SMM) [26].…”