| Abstract
| - The complexes [Cu2(dpt)2Cl2]X2 (dpt = dipropylenetriamine; X = Cl, 1; X2 = (Cl)(BPh4), 2) have been preparedand their magnetic properties studied. The crystal structure of complex 1 has been solved. The compound belongsto the C2/c space group with Z = 4, a = 17.201(2) Å, b = 10.873(2) Å, c = 11.835(2) Å, and β = 99.720(10)°.The geometry about each copper approximates that of a distorted square pyramid. The three N-atoms of the dptligand and one of the Cl bridging ligands form the base of the pyramid while the other chloro bridging ligandoccupies the axial site. The two pyramids share a base-to-apex edge with the basal planes being perpendicular,an arrangement which had not been previously observed for this type of dimers. The chloro counterions areresponsible for interdimer interactions through hydrogen bonding forming chains of dimers throughout the lattice.Magnetic susceptibility data show a ferromagnetic coupling between the two Cu(II) centers (J = 42.94 cm-1 for1 and J = 13.89 cm-1 for 2). Dimer−dimer interaction and ZFS have been considered with the J‘ parameter (1,J‘ = −3.92 cm-1; 2, J‘ = −2.9 cm-1). Extended Hückel calculations on complex 1 clearly reveal that the intradimermagnetic interaction only takes place through the basal chloro bridging ligand (with a CuCl(1)Cu angle of 91.4°)which in turn is consistent with the observed ferromagnetic coupling.
- A new dinuclear copper(II) complex with chloro-bridging ligands [Cu2(dpt)2Cl2]Cl2 has been prepared and structurally and magnetically characterized. The structure of this complex is very unusual and consists of two square pyramids sharing a base-to-apex edge. Magnetic studies for this complex show the presence of a strong intradimer ferromagnetic coupling (J = 42.94 cm-1) and a weak interdimer antiferromagnetic coupling (J‘ = − 3.92 cm-1) that takes place through Cl counterions throughout the lattice.
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