Hybrid materials containing organometallic cations and 3-D anionic metal dicyanamide networks of type [Cp*M-2][M '(dca)(3)]

A new series of hybrid materials of type [Cp*M-2][M'(dca)(3)] has been prepared by cation templation and structurally characterised (M = Fe(III), Co(III); M' = Mn(II), Fe(II), Co(II), Ni(II), Cd(II); dca(-) = N(CN)(2)(-)). The crystallographic analysis of [Cp*Fe-2][Cd(dca)(3)] showed that the [Cd(dca)(3)](-) anionic framework is of a symmetrical 3-D alpha-polonium type, containing octahedral Cd nodes and mu(1,5)-dca bridging ligands. The [Cp*Fe-2](+) cations occupy the cube-like cavities within the framework. The cationic and anionic-framework sublattices remain magnetically independent and display susceptibilities, over the range 300 to 2 K, of a Curie-Weiss nature obtained by adding a S = 1/2 (Cp*Fe-2(+)) or a S = 0 (Cp*Co-2(+)) contribution to those of the weakly antiferromagnetically coupled frameworks of M'. These hybrid species do not show any intrinsic long-range magnetic order. The present [Cp*Fe-2][M'(dca)(3)] series display the characteristic, unusually shaped [Cp*Fe-2](+) Mossbauer line, in the range 295-5 K, assigned (below 101 K) as the sum of a narrow and a broad line. Relaxation effects were evident. The [Fe(dca)(3)](-) compound showed superimposed low-spin Fe(III) and high-spin Fe(II) lines, the latter giving relaxation broadening effects.