A new co-crystal dinuclear/trinuclear ZnII-ZnII/ZnII-SmIII-ZnII complex with a salen-type Schiff base ligand.

ABSTRACT

In the penta-nuclear title complex, [SmZn2(C22H18N2O4)2(NCS)2(C3H7NO)2][Zn2(C22H18N2O4)(NCS)3]·C3H7NO·0.32H2O, namely bis-{µ2-6,6'-dimeth-oxy-2,2'-[phenyl-ene-1,2-diylbis(nitrilo-methanylyl-idene)]diphenolato}-1κ4 O,N,N',O'2κ3 O,O',O 6;2κ3 O,O',O 63κ4 O,N,N',O'-bis-(di-methyl-formamide-2κO)di-thiocyanato-1κN,3κN-2-samarium(III)-1,3-dizinc(II) {µ2-6,6'-dimeth-oxy-2,2'-[phenyl-ene-1,2-diylbis(nitrilo-methanylyl-idene)]diphenolato-1κ4 O,N,N',O'2κ2 O,O'}trithio-cyan-ato-1κN;2κ2 N,N-dizinc(II) di-methyl-formamide monosolvate 1.32-hydrate, a dinuclear unit and a trinuclear unit co-exist. One of the ZnII centers in the dinuclear unit as well as the two ZnII centers in the trinuclear unit are located in the inner N2O2 cavity of the ligand and are coordinated to the nitro-gen atom of one thio-cyanate moiety, giving rise to a square-pyramidal geometry. The second ZnII center in the dinuclear unit is coordinated to the two phenolate oxygen atoms of the ligand and to two thio-cyanate groups via the nitro-gen atom in a tetra-hedral geometry. The SmIII ion is eight-coordinated by four phenolate O atoms from the two ligand mol-ecules, two meth-oxy O atoms from the two ligand mol-ecules and two O atoms from the DFM solvent mol-ecule. In the dinuclear unit, the two meth-oxy oxygen atoms remain uncoordinated while in the trinuclear unit, for each ligand one meth-oxy oxygen is coordinated and the other one remains uncoordinated. In the crystal, the trinuclear cationic units and dinuclear anionic units are assembled into infinite layers. These layers are held together via electrostatic inter-actions, forming a three-dimensional structure. In the dinuclear unit, the C and S atoms of one of the thio-cyanate groups are disordered over two sets of sites in a 0.680 (4)(4)0.320 (4) ratio.