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Nanocomposites showing superparamagnetic properties have been synthesized from imine polymers. The method for the production of the nanocomposites is very simple. The imine polymer reacts with a metal salt and the product is dried. Apparently, the reaction of polymer grains with a metal solution takes place by a surface reaction mechanism. Metal hydroxides precipitate within the polymer matrix without addition of a base or of an oxidizer since the polymer imine groups provide a basic medium. The metal oxides are formed through hydrolysis of the metal hydroxides when drying. The method works the best for imine polymers with a flexible chain and no hydrophobic branches. Several iron and cobalt salts, as well as a manganese salt, have been used in the procedure. The effect of the solvent and of the metal salt counterion on the procedure has been studied.

The preparation of tungsten iodides in large quantities is a challenge because these compounds are not accessible using an easy synthesis method. A new, remarkably efficient route is based on a halide exchange reaction between WCl6 and SiI4. The reaction proceeds at moderate temperatures in a closed glass vessel. The new compounds W3I12 (W3I8 ⋅2 I2) and W3I9 (W3I8 ⋅½I2) containing the novel [W3I8] cluster are formed at 120 and 150 °C, and remain stable in air. W3I12 is an excellent starting material for the synthesis of other metal-rich tungsten iodides. At increasing temperature these trinuclear clusters undergo self-reduction until an octahedral tungsten cluster is formed in W6I12 . The synthesis, structure, and an analysis of the bonding of compounds containing this new trinuclear tungsten cluster are presented.

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The ternary carbodiimides Li 2 Sn(CN 2 ) 3 , Na 2 Sn(CN 2 ) 3 , Li 2 Zr(CN 2 ) 3 and Li 2 Hf(CN 2 ) 3 were synthesized and their crystal structures were solved and refined by means of powder X-ray diffraction [Li 2 Zr(CN 2 ) 3 and Li 2 Hf(CN 2 ) 3 crystallize in R3c, whereas Li 2 Sn(CN 2 ) 3 and Na 2 Sn(CN 2 ) 3 crystallize in Pnna]. All structures are characterized by alternating layers of carbodiimide units and metal atoms, although cations show distinct Salt-like metal dinitridocarbonates are established by various examples of metals, in which the (NCN) 2ions appear with the carbodiimide ([N=C=N] 2-) or cyanamide ([N≡C-N] 2-) shape.Carbodiimide and cyanamide ions are frequently considered as pseudo chalcogenides, due to their divalent anion charge. This assignment appears useful when a close structural relationship is given, as for the couple Y 2 O 2 (CN 2 ) and Y 2 O 2 S. [1] Not only the well-known Y 2 O 2 S:Eu but also Y 2 O 2 (CN 2 ):Eu exhibit remarkable photoluminescence properties. [1,2] Alkali and alkali earth carbodiimide compounds are well known, and binary carbodiimides of the transition metals are established for Cr-Zn, [3] Ag, [4] Cd [5] and Hg [6] with oxidation states of +I, +II or +III. Fe(CN 2 ) was reported for its reversible Li + and Na + intercalation properties and considered as potential cathode materials for batteries. [7] Recently, the ternary carbodiimide SrZn(CN 2 ) 2 containing both, a main group-and posttransition metal was discovered. [8] Binary carbodiimides of rare earth elements are reported as RE 2 (CN 2 ) 3 for RE = Y, La-Lu (except Pm). Some lanthanide doped compounds, RE 2 (CN 2 ) 3 /Ln with Ln = Ce, Tb, Eu, are known for their photoluminescence. [9] Another family of compounds is represented by the cyanamidometallates whose complex anions [T(CN 2 ) 4 ] 4with T = Si, Ge and [T(CN 2 ) 4 ] 5with T = Al, Ga can be derived from (SiO 4 ) 4and (AlO 4 ) 5anions. [10] [a]

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