Crystal structures and magnetic properties of Ni-bisdithiolene complexes with decamethylmetallocenium cations

Three new compounds of formula (1), (2), and (3) have been synthesised, and structurally and magnetically characterised (dmit²⁻ = 1,3-dithiol-2-thione-4,5-dithiolato; dmid²⁻ = 1,3-dithiol-2-one-4,5-dithiolato). Their structural features and magnetic behaviours are compared with those of and . The result of this is that the interactions between the Ni(dmit)₂ units in 1 are of ferromagnetic-type, as suggested previously for . The change from acetonitrile to acetone when going from to 2 results in stronger ferromagnetic intermolecular interactions. This better cooperativity is due to a significant increase of the number of contacts between the various moieties within the . On the contrary, the inclusion of larger solvents such as benzonitrile in this type of complexes results in a totally different structural arrangement, which leads to an antiferromagnetic behaviour for 3.     

Dinuclear gold(III) pyrazolato complexes - Synthesis, structural characterization and transformation to their trinuclear gold(I) and gold(I/III) analogues

The reaction of AuCl₃py with Na(pz∗) (pz∗ = pyrazolato, or substituted pyrazolato anion) yields stable dinuclear [cis-Au^IIICl₂(μ-pz∗)]₂ complexes. In the presence of a base, the latter undergo reduction with concomitant transformation of the dinuclear -structure to trinuclear Au^I, Au^III (containing trans Au^IIICl₂-centres) and species.