Magnetic partial oxidation

A recent report of Hill et al. (192) states that the low values of the magnetic susceptibility of Mn(Et2rftc)2 obtained by Lahiry and Anand are due to partial oxidation of the sample and that the compound has a sextet ground state. The dimeric [Mn(Et2C tc)2]2 is not X-ray isomorphous with Ni(Et2< tc)2, but gives a powder pattern similar to, though not identical with Cu(Et2[Pg.95]

In contrast, (BDTA)[Ni(dmit)2]2 has been fully characterized [89] (X-ray structure, magnetic susceptibility data, band structure and conductivity). It exhibits an SC behavior with a room-temperature conductivity of 0.1 S cm-1. Its magnetic behavior is dominated by AFM interactions, probably due to the coupling between the Ni(dmit)2 moieties. Although its properties are not spectacular, this complex is the first well-characterized example of a salt containing partially-oxidized Ni(dmit)2 moieties with a radical cation. 

The search for bi-functionality in molecular materials constitutes a contemporary challenge in materials science. Using the two-network approach described in the previous section it has been possible to construct hybrid crystalline solids formed by a partially oxidized jt-electron donor network that support electronic conductivity or even superconductivity, and transition metal complexes containing magnetic moments. Some... 

The following is a case history of the one-dimensional inorganic complex, K o.5lr(CO)2Cl2, which exhibits high conductivity at room temperature. This complex exhibits a variety of unusual properties which indicate a columnar structure and a partially oxidized character in spite of the original proposals for its structure. This material serves as an instructive example to point out several features which make the complex worthy of detailed study. To date, the detailed study of its electrical, magnetic, and optical properties has not been reported. 

Recently Krogmann et al postulated a cation-deflcient, partially oxidized formulation for this material, K o.5lr(CO)2Cl2, and a columnar structure in the solid (16). This one-dimensional structure is consistent with the observed diamagnetism, stoichiometry, IR spectra, dc conductivity, and visual appearance of the complexes. Preliminary powder x-ray data support this formulation with a short 2.86 A Ir-Ir distance. This information sets a basis for the interpretation of detailed optical, electrical, and magnetic measurements that will help in further understanding of the chemistry and physics of one-dimensional inorganic complexes. 

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