The first cyano-bridged heptanuclear Mn(III)6Fe(III) cluster:: crystal structure and magnetic properties of [{Mn(salen)•H2O6Fe(CN)6][Fe(CN)6]•6H2O

Reaction of K-3[Fe(CN)(6)] with [Mn(salen).H2O]ClO4.H2O (salen: N,N'-ethylenebis(salicylideneiminato) dianion) affords a bimetallic heptanuclear complex cationic salt [{Mn(salen).H2O}(6)Fe(CN)(6)][Fe(CN)(6)].6H(2)O. In the complex cation [{Mn(salen).H2O}(6)Fe(CN)(6)](3+), the central [Fe(CN)(6)](3-) unit is surrounded by six [Mn(salen).H2O](+) moieties through Fe-C-N-Mn linkages with dimensions of Fe-C = 1.941(5) Angstrom, Mn-N = 2.334(2) Angstrom, Fe-C-N = 177.7(2)degrees and Mn-N-C = 150.7(1)degrees. The variable temperature magnetic susceptibilities, measured in the 5-300 K range, indicate the presence of a weak intracluster ferromagnetic interaction between Fe(III)(S = 1/2) and Mn(III)(S = 2) through cyano bridges. (C) 2003 Elsevier B.V. All rights reserved.