Synthesis, crystal structure and magnetic properties of a mixed-valence pentanuclear cobalt complex

Solvothermal reaction of Co(OAc)(2)center dot 4H(2)O with H(4)L (H = 2-((2-hydroxybenzylidene)amino)-2-hydroxymethylpropane-1,3-diol) in MeCN gave a mixed-valence pentanuclear cobalt complex [Co(5)(HL)(2)(H(2)L)(2)(OAc)(2)]center dot 2.5H(2)O. Crystal structural analysis revealed that two Co(III) ions were linked to a central triangular Co(II) core through HL(3-) and H(2)L(2-) hydroxyl groups. Magnetic measurements showed interesting magnetic properties that were assigned to spin-orbital coupling and ferromagnetic exchange interactions.