title: Synthesis, crystal structures, and magnetic properties of cyano-bridged honeycomblike layers M(V)-Cu(II) (M = Mo, W) chelated by a macrocyclic ligand.
abstract: Two cyano-bridged Cu(II)-M(V) [M = Mo (2), W (3)] complexes formed by self-assembly of octacyanometalates [M(CN)8]3- (M = Mo, W) with a new molecular precursor [Cu(L2)]2+ (1) (L2 = a macrocyclic ligand) in a 2:3 ratio have been investigated in terms of structures and magnetic behaviors. The M2Cu3 repeating unit of both bimetallic compounds is extended to a two-dimensional honeycomblike layered structure. The pendant ethyl groups on L2 noticeably influence the structural parameters around the Cu center. Compared with the system composed of a macrocycle without a side group, Cu-N(ax) (ax = axial) distances become shorter and the Cu-N(ax)-C(ax) angles are more bent for 2 and 3. The magnetic data denote that the Cu(II) and M(V) spins undergo explicit ferromagnetic interactions via CN bridges. From a structural and magnetic point of view, given that the Cu-N(ax) bond length in the tetragonally distorted octahedral Cu(II) environment is long enough, the overall ferromagnetic character remains despite the variation of Cu-N(ax)-C(ax) angle in this system.
authors.affiliation: Department of Chemistry and Center for Electro- and Photo-Responsive Molecules, Korea University, Seoul 136-701, Korea.
authors.forename: Jeong Hak
authors.initials: JH
authors.lastname: Lim
authors.forename: Jun Sung
authors.initials: JS
authors.lastname: Kang
authors.forename: Hyoung Chan
authors.initials: HC
authors.lastname: Kim
authors.forename: Eui Kwan
authors.initials: EK
authors.lastname: Koh
authors.forename: Chang Seop
authors.initials: CS
authors.lastname: Hong