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Crystals of the complex Per2M(mnt)2, where M = Fe and Co and mnt = maleonitriledithiolate, were prepared through electrocrystallization. These complexes differ from the series M = Au5, Pd5, Pt1, Ni6 and Cu6 in the doubled b parameter along the stacking axis. The residual electron density near the Fe atom is assumed to indicate the dimerization of the Fe(mnt)2 units. Per2Fe(mnt)2 consists of separate layers of perylene and Fe(mnt)2 packed like those in the other metals. The high temperatures and transport properties of both compounds are similar to the other metallic members.

The syntheses, structural and magnetic characterization of the compounds of formula [[[Fe.sup.III](Sa[I.sub.2]trien)].sub.2][[Mn.sup.II.sub.2][(ox).sub.3]].4[H.sub.2]O.[C.sub.3][H.sub.7]NO and [[[In.sup.III]-(sa[I.sub.2]trien)].sub.2][[Mn.sup.II.sub.2][(ox).sub.3]].3[H.sub.2]O.C[H.sub.3]OH are reported. The compounds showed coexistence of a magnetic ordering of the Mn(II) oxalate network that behaves as a weak ferromagnet and a gradual spin crossover of the intercalated [[Fe(sa[I.sub.2]trien)].sup.+] complexes.

The synthesis and magnetic properties of the oxalate-based molecular soluble magnets with general formula [[K(18-crown-6)].sub.3][[[M.sup.II.sub.3][([H.sub.2]O).sub.4][{[M.sup.III][(ox).sub.3]}.sub.3].sub.3]] ([M.sup.III] = Cr, Fe; [M.sup.II] = Mn, Fe, Ni, Co, Cu; ox = [C.sub.2][O.sub.4.sup.2-]; 18-crown-6 = [C.sub.12][H.sub.24][O.sub.6]) are described. The isostructural compounds are built by two dimensional bimetallic networks formed by alternating [M.sup.III] and [M.sup.II] ions connected through oxalate anions and [Cr.sup.III][M.sup.II] derivatives behave as ferromagnets with temperatures up to 8 K, the [Fe.sup.III] [M.sup.II] exhibit ferri- or weak ferromagnetic properties up to 26 K.

The thermally stable complexes containing the corresponding radical anion/ketyls which were obtained by the reaction of [Sm[([TP.sup.Me2]).sub.2] with benzophenone, fluorenone, di-tert-butylparaquinone, and di-tert-butylorthoquinone is reported.

A general protocol to access Mo(3)FeS(4)(4+) clusters selectively modified at the Fe coordination site is presented starting from the all-chlorine Mo(3)(FeCl)S(4)(dmpe)(3)Cl(3) (1) [dmpe = 1,2-bis(dimethylphosphane-ethane)] cluster and tetrabutylammonium salts (n-Bu(4)NX) (X = CN(-), N(3)(-), and PhS(-)). Clusters Mo(3)(FeX)S(4)(dmpe)(3)Cl(3) [X = CN(-) (2), N(3)(-) (3), and PhS(-) (4)] are prepared in high yield, and comparison of geometric and redox features upon modification of the coordination environment at the Fe site at parity of ligands at the Mo sites is also presented. The existence of the cubane-type Mo(3)FeS(4)(4+,5+) redox couple is demonstrated by cyclic voltammetry and for compound 1 by cluster synthesis and X-ray structure determinations. Ground states for the 1/1(+) redox couple are evaluated on the basis of magnetic susceptibility measurements, electron paramagnetic resonance, and (57)Fe Mössbauer spectroscopy aimed at providing an input of experimental data for electronic structure determination based on density functional theory calculations.