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Salts containing the dinuclear anion (M(sub.2)Cl(sub.6))(super.2-) (M = Mn, Fe, Co) are discussed relative to magnetic properties, structures and reactivities. The edge-sharing bitetrahedral anion was isolated with 5 different cations. The electronic ground state of the ion is orbitally degenerate and highly anisotropic, a conclusion confirmed with magnetic data. The bridging ligand mediates antiferromagnetic exchange. The D parameter is large and negative. High-spin polynuclear transition metal compounds are of interest for magnetic properties for biological use and for materials chemistry. Iron, or ferrous, compounds have not been studied well vs ferric systems.

The synthesis and characterization of two new, highly soluble, single-molecule magnets are reported. The substitution of the acetate ligands buy trifluoroacetic acid was monitored by mass spectrometry, which is a convenient tool for judging completion of the substitution process.

X-ray crystallography, infrared spectroscopy and magnetic measurements were employed to characterize (Mn(TCNQ-TCNQ)(MeOH)2.MeOH)(sub infinity) and (Mn(TCNQ)(TCNQ-TCNQ)0.5(MeOH)2)(sub infinity). The former, which was obtained as blue triclinic parallelipipeds, and the latter, which was prepared are purple monoclinic needles. contain unique arrangements of manganese ions and ligands derived from (7,7,8,8-tetracyanoquinodimethane)(sup -.). In addition, the latter has a ferromagnetic transition at around 50 K.

Research was conducted to examine the syntheses and characterization of two polymorphs of Cu(TCNQ). Infrared spectroscopy, single-crystal X-ray methods, powder X-ray diffraction techniques and X-ray photoelectron spectroscopy were used for the experiments. The properties of the two phases were compared to several films of Cu(TCNQ). Results indicate that Cu(TCNQ) phase I is a good semiconductor with a room-temperature conductivity of 0.25 S/cm while Cu(TCNQ) phase II is a very poor semiconductor.