A tetranuclear Cr(III)Ni(II)3 cyano-bridged complex based on M(tacn) derivative building blocks

The reaction of Cr(Bztacn)(CN)3 (Bztacn is 1,4,7-trisbenzyl-1,4,7-triazacyclononane) with Ni(iPrtacn)Cl2 (iPrtacn is 1,4,7-trisisopropyl-1,4,7-triazacyclononane) affords a CrNi3 tetranuclear complex. Variable temperature and magnetization versus field measurements show a S = 9/2 ground state and an appreciable magnetic anisotropy with a negative D(9/2) value equal to -0.54 cm(-1). Magnetization studies on one single crystal using a micro-SQUID show a fast tunneling process at zero field at very low temperature.