Synthesis and characterization of tetrakis(mu-hydroxo)itetrakis(2,2 '-dipicolylamine)tetranickel perchlorate, a nickel-hydroxy cubane complex

摘要

A novel tetranuclear complex, [Ni(mu(3)-OH)(DPA)](4)(ClO4)(4) (where DPA = 2,2'-dipicolylamine) has been synthesized, with characterization including electronic and infrared spectroscopy, elemental analysis, mass spectrometry, crystal structure analysis, and variable-temperature and variable-field magnetic susceptibility measurements. The complex features a 4Ni-4OH cubane-type cluster, displaying both ferromagnetic and antiferromagnetic intracluster interactions in a 2J model (J(1) = -3.4 cm(-1), J(2) = 4.7 cm(-1), D = 2.0 cm(-1)). Each nickel atom sits in a pseudooctahedral environment, with one DPA molecule facially coordinated and the remaining three coordination sites occupied by the bridging hydroxide anions that make up the cubane core. (C) 2007 Elsevier B.V. All rights reserved.