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Research demonstrates the synthetic, structural, and magnetic properties of oxalato-bridged bimetallic magnets. Data show that the compounds are isostructural with cubic space group made of three-dimensional bimetallic network of M(sup)II and chromium(sup)III ions which in turn bridged by oxalateanions.

Research discusses the synthesis, crystallization, and structural analyses of four coordination compounds that contain bimetallic cyanide-bridged complexes. Data show that the compounds crystallize in the monoclinic or triclinic or tetragonal space group with quasi-isolated paramagnetic nickel or manganese.

An organic/inorganic hybrid salt is obtained by combination of the photochromic nitroprusside complex with the organic donor TTF (tetrathiafulvalene). The organic part shows an unprecedented 2D organization formed by an orthogonal arrangement of TTF hexamers and monomers.

Addition of organometallic radical cations derived from ferrocene to various polyanions having the Keggin structure produces a new family of molecular materials. Structural studies of these compounds reveal the existence of two types of structures, a one dimensional type with chains of organometallic radicals and a second type having radicals in a three dimensional array. Examination of the magnetic properties of these compounds reveals the absence of significant magnetic exchange interactions between the two parts, which is confirmed by EPR studies.

Single-crystal X-ray studies help characterize structures of Mn(II) and Ni(II) complexes of the type (M4(H2O)2(P2W15O56)2)(16-), which are isostructural with the related Cu(II) and Zn(II) derivatives. The complexes have a rhomblike M4O16 group between two fragments of the trivacant Dawson-Wells polyanion (P2W15O56)(12-). The Mn(II) complex shows antiferromagnetic Mn-Mn exchange interactions while the Ni(II) complex exhibits ferromagnetic exchange interactions within the Ni4O16 group. The Ni(II) complex exhibits the highest spin state in a heteropoly complex.

The encapsulation of magnetic clusters of the transition metal ions between diamagnetic fragments of metal oxides is a major characteristic of polyoxometalate complexes. The reaction of divalent metal ions with the trivalent tungstophospate ligands produces new types of compounds. These compounds are derived from the Keggin and Dawson-Wells polyoxoanions. The tetrametallic unit M4O16 is encapsulated by the individual polyoxometalate entities.

Crystals of a heteropolytungstate compound with the formula K5.5Na1.5(PW10Cu2 H2O 2O38).13H2O were subjected to X-ray diffraction, magneticsusceptibility and electronparamagnetic resonance spectroscopy examinations. Structural data identified the predominant alpha-Keggin coordination taken by the compound and the location of the copper ions. In addition, the exchange-coupled copper pairs, which were confirmed using magnetic measurements, formed two different exchange interactions and two anisotropies for the compounds.

The synthesis, structure, and physical properties of BIS(ethylenedithio)tetrathiafulvalene Ni(1,2,5-thiadiazole-3,4-dihiolate)2 [(BEDT-TTF)[Ni(tdas)2], which is the first example of a salt containing monomeric [Ni(tdas)2](super -) monoanions, are reported. It can be concluded that the unpaired electron lies on the [Ni(tdas)2](super -) anions.