Binuclear Nickel(II) Complexes Based on Bridging Oxalate and Pseudohalides as Peripheral Ligands: Synthesis, Crystal Structure, DFT Calculations and Magnetic Properties of [{Ni(X)(dien)}_2(#mu#-ox)].nH_2O Complexes (X=N_3~-, NCS~-, n=0;NCO~-,n=1)

摘要

Nickel(II) molecular complexes were obtained by water displacement reactions of [{Ni(dien)(H_2O)}_2(#mu#-ox)]Cl_2 and the corresponding pseudohalide. The three nickel(II) compounds [{Ni(N_3)(dien)}_2(#mu#-ox)] (1), [{Ni(NCO)(dien)}_2(#mu#-ox)].H_2O (2) and [{Ni(NCS)(dien)}_2(#mu#-ox)] (3) are almost isostructural. The structure determinations reveal the presence of a binuclear complex with C_(2h) symmetry, where the oxalate ligand is coordinated in a bis(bidentate) fashion to the twofold related nickel atoms. The distorted octahedral environment of each nickel atom is completed by the three nitrogen atoms of the diethylenetriamine ligand in a fac arrangement and one nitrogen aotm from a pseudohalide ligand. Magnetic susceptibility data in the temperature range 4.2-300 K shows intramolecular antiferromagnetic coupling.