A novel chloro-bridged tetranuclear cadmium(II) cluster with pyridyl-substituted nitronyl nitroxide: structure and magnetic properties

A tetranuclear cadmium(II) complex of 2(2-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1 H-imidazol-1-oxy 3-N-oxide (NIToPy) with CdCl2,[Cd4Cl8(NIToPy)4], has been structurally and magnetically characterized. The structure is based on a novel chloro-bridged tetranuclear cadmium quasi-cubane cluster, in which each cadmium atom is chelated by one NIToPy radical, and coordinated with four bridging chlorine atoms. The temperature dependence of the magnetic susceptibility measurements shows a weak ferromagnetic coupling between the radicals. An excellent simulation of the experimental data with the prism type four spins Hamiltonian H=−2J1(S1S2+S2S3+S3S4+S1S4)−2J2S2S4 obtained the parameters: J1=1.12 cm−1, J2=−0.20 cm−1, and g=2.04.