A unique tridecanuclear Co(II) cluster with derivatised salicylaldoxime ligands: Structure, electrospray ionization mass spectrometry analysis and preliminary magnetic studies

A unique [Co13(mosao)8(Hmosao)6]·(ClO4)4·3DMF·MeOH·3H2O (1, H2mosao = 3-methoxysalicylaldoxime) supercluster has been synthesized by a method of solvothermal reaction. The [Co13(μ2-O)8(μ3-O)6(μ2-O–N)2(μ3-O–N)8]4+ core is highly conjugated butterfly-like disc, which can be considered as fourteen distorted defective cubes sharing the neighboring faces one another. The electrospray ionization mass spectrometry (ESI-MS) analysis of 1 strongly suggests that Co13 cluster also exists in solution and maintains a conformation similar to that in the crystal structure, indicating that the significant stability of 1 in solution. Magnetic measurements of 1 reveal antiferromagnetic behaviors resulting from the cooperative magnetic coupling through multiplicate monoatomic oxygen and –N–O– exchange bridges and the odd number of spins result in relatively effective noncompensated moments at very low temperature.

A unique tridecanuclear cluster contains the butterfly-like [Co13(μ2- O)8(μ3-O)6(μ2-O-N)2(μ3-O-N)8]4+ core with mixed monoatomic oxygen and diatomic –N–O– intracluster superexchange bridges, which exhibits significant high stability in solution via the ESI-MS analysis. The odd number spins of Co13 cluster result in relatively effective noncompensated moments at low temperature in spite of intracluster antiferromagnetic coupling.Figure optionsDownload as PowerPoint slide