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[Fe-4(III)(acac)(6)(Br-mp)(2)] (1) and [Fe-4(III)(acac)(6)(tmp)(2)] (2) were obtained from the reaction of Fe(acac)(2) with the appropriate tripodal alcohol. Both magnetic clusters show clear signatures for ferrimagnetic super exchange coupling. A fit of the DC susceptibility of 1 with the Kambe model gives J = -8.2 +/- 0.2 cm(-1), with g = 1.96 +/- 0.02. Powder AC susceptibility data display significant frequency dependence for both compounds. The observation of an out-of-phase component demonstrates that these molecules may be single-molecule magnets (SMMs). AC susceptibility data for frozen solutions of 1 and 2 in toluene also show an out-of-phase signal proving these molecules are SMMs in solution. Going from powder to solution, the chi '' signals shift to higher temperatures which points towards an increase in energy barrier for the magnetization relaxation. (C) 2009 Elsevier Ltd. All rights reserved.