Syntheses and characterization of two novel heptanuclear trigonal prismatic LnNi6 clusters with different terminal ligands

Abstract: Two novel heptanuclear trigonal prismatic LnNi6 clusters, [SmNi6(Gly)6(Ac)(μ3-OH)3(μ2-H2O)2(im)6]·(ClO4)5 ·(H2O)5 (1) and [GdNi6(Gly)6Cl3(OH)3(py)6]·Cl·(ClO4)2 ·(H2O)5 (2), were synthesized through self-assembly, and were characterized by X-ray structure analyses. Complex 1 crystallizes in the monoclinic Cc space group (a =17.9722(3) Å, b =16.3906(2) Å, c =25.3463(3) Å, β =99.832(1)° and Z =4). Complex 2 attributes to the monoclinic P2(1)/c space group (a =15.5408(2) Å, b =20.0516(4) Å, c =23.8204(4) Å, β =100.096(1)° and Z =4). 1 has six terminal imidazole ligands, while 2 has six terminal pyridine ligands. The two complexes both have a [LnNi6(Gly)6(μ3-OH)3]6+ core. The magnetic measurements reveal that 1 exhibits an overall antiferromagnetic interaction, while 2 exhibits a ferromagnetic interaction. [Copyright &y& Elsevier]