Structure and magnetic property of a mixed-valence nonanuclear cobalt compound with a square-pyramidal CoII5coreCCDC reference number 720927. For crystallographic data in CIF or other electronic format see DOI: 10.1039/b903733k.

A novel cobalt compound [Co9(HL)4(L)4Cl2]·(EtOH)2(H2O)2(H3L= (E)-2-2((1,3-dihydroxy-2-methylpropan-2-ylimino)methyl) phenol) has been solvothermally synthesized and structurally characterized. The compound crystallised in the space group C2/cwith a= 32.624(2) Å, b= 9.4814(4) Å, c= 33.395(2) Å, β= 109.339(5)° and V= 9746.8(9) Å3. The crystal structure is a mixed-valence nonanuclear Co(II/III) oligomer, which contains a square-pyramidal CoII5core formed through μ4-Cl and μ3-alkoxo bridges and the pentanuclear CoII5core is surrounded by four peripheral Co(III) ions at the square-pyramidal base plane through μ2-alkoxo bridges. Magnetic properties of the compound can be considered as the magnetism of the CoII5core, and the superexchange interactions between Co(II) ions within the core were calculated with three Co(II)–Co(II) superexchange parameters by using MAGPACK software package to give J1= + 11.1 cm−1, J2= −6.50 cm−1, J3= −3.25 cm−1, D= + 6.0 cm−1and g= 2.30. [ABSTRACT FROM AUTHOR]