Octacyanotungstate(v)-based square W(2)M(2) (M = Co, Mn) complexes: synthesis, structure and magnetic properties.

The preparation, single-crystal X-ray crystallography and magnetic properties are reported for two tetranuclear cluster complexes based on W(V)(CN)(8) octacyanometallates. Reactions of W(V)(CN)(8) with Co(II) ions in the presence of the capping ligand tpm (tpm = tri(1H-pyrazol-1-yl)methane) lead to the formation of complex 1 [(tpm)(2)Co(II)][W(V)(2)(CN)(16)Co(2)(tpm)(2)(H(2)O)(2)].4H(2)O. Analogous reactions with the Mn(II) produce complex 2 [(tpm)(2)Mn(II)][W(V)(2)(CN)(16)Mn(2)(tpm)(2)(H(2)O)(2)].4H(2)O. Complexes 1 and 2 are isomorphous and crystallize in the space group of P1[combining macron]. Magnetic investigation shows the ferromagnetic coupling between Co(II) and W(V) ion in complex 1, while the antiferromagnetic interactions between Mn(II) and W(V) in complex 2. Further magnetic studies indicate the presence of spin glasses in complex 2, which may be attributed to the further ferromagnetic coupling between anionic and/or cationic cores.