Synthesis, crystal structure and magnetic properties of trithiocyanurate or thiodiacetate polynuclear Ni(II) and Co(II) complexes

Three new polynuclear complexes [Ni-2(pmdien)(2)(H2O)(2)(mu-tda)](ClO4)(2)center dot 2H(2)O (1), [Ni-7(pmdien)(6)(H2O)(2)(mu-ttc)(3)](ClO4)(5)center dot 3H(2)O (2) and [Co-3(pmdien)(3)(mu-ttc)](ClO4)(3) (3) (pmdien = N,N,N',N '',N ''-pentamethyldiethylenetriamine, ttc(3) = trithiocyanurate(3) anion, tda(2) = thiodiacetate(2) anion) have been prepared and characterized structurally and magnetically. The X-ray structure of heptanuclear Ni(II) complex revealed three hexa and four pentacoordinated nickel cations connected by trithiocyanuarate bridge, forming a regular Ni(7)(II)core. The composition of 3 was determined by ESI-MS spectra and DFT calculation. Magnetic susceptibility data over the 1.8-300 K temperature range along with the magnetization data up to B = 5 T showed antiferromagnetic interactions: J/hc = -0.65 cm (1) for 1; -6.1 and -6.5 cm (1) for 2; -0.001 cm (1) for 3. The magnetic susceptibilities of all antiferromagnetic complexes were fitted by using approximate models. (C) 2014 Elsevier B.V. All rights reserved.