Synthesis, molecular structure, and magnetic properties of [CuLNi(H2O)2LCu][ClO4]2�4H2O [H2L =N,N?-bis(3-amino-2,2-dimethylpropyl)oxamide] and its trinickel homologue

The compounds [MLNi(H2O)2LM][ClO4]2.4H2O [M = Cu or Ni; H2L = N,N'-bis(3-amino-2,2-dimethylpropyl)oxamide] were prepared and characterized by means of structural, magnetic and spectroscopic measurements. The crystals of both compounds are triclinic, space group P1BAR and Z = 2, with a = 12.080(1), b = 13.054(1), c = 14.775(2) angstrom, alpha = 101.97(1), beta = 90.82(1) and gamma = 101.88(1)-degrees, for M = Cu and a = 12.099(5), b = 13.060(4), c = 14.750(7) angstrom, alpha = 101.98(3), beta = 90.28(4) and gamma = 102.25(3)-degrees for M = Ni. The structural unit of both complexes consists of trinuclear dipositive cations, two perchlorate anions and four lattice water molecules. The central and terminal metal ions are antiferromagnetically coupled, J = 90(1) cm-1 in the case of M = Cu.