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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.

Abstract: Aluminum incorporation in the rhombohedrally distorted perovskite lattice of (La0.5Sr0.5)1− x Fe1− y AlyO3− δ (, ) decreases the unit cell volume and partial ionic and p-type electronic conductivities, while the oxygen nonstoichiometry and thermal expansion at 900–1200K increase on doping. The creation of A-site cation vacancies has an opposite effect on the transport properties of Al-substituted ceramics. The maximum A-site deficiency tolerated by the (La,Sr)(Fe,Al)O3− δ structure is however limited, close to 3–4%. The Mössbauer spectroscopy revealed progressive localization of electron holes and a mixed charge-compensation mechanism, which results in higher average oxidation state of iron when Al3+ concentration increases. The average thermal expansion coefficients of (La0.5Sr0.5)1− x Fe1− y Al y O3− δ are (12.2–13.0)×10−6 K−1 at 300–900K and (20.1–30.0)×10−6 K−1 at 900–1200K in air. The steady-state oxygen permeability (OP) of dense Al-containing membranes is determined mainly by the bulk ionic conductivity. The ion transference numbers at 973–1223K in air, calculated from the oxygen permeation and faradaic efficiency (FE) data, vary in the range 1×10−4–3×10−3, increasing with temperature. [Copyright &y& Elsevier]

The title compound is synthesized by reduction of Sr4Fe6O13.+-.δ with excess CaH2 (evacuated pyrex tube, 493 K, 7 d) and characterized by X-ray and neutron powder diffraction, magnetic susceptibility measurements, and Moessbauer spectroscopy. [ABSTRACT FROM AUTHOR]