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We have synthesized a bicopper(II) complex of N,N′,N″,N‴-tetra(2-aminoethyl)-1,1,2,2-ethanetetraamide and determined its crystal structure by X-ray diffraction. The complex has two dioxotetraamine sub-units linked by a CC bond. Each copper is situated in a square-pyramid consisting of four nitrogen atoms and one water molecule. The nitrogen atoms of the amido groups have stronger coordination ability than those of amino groups because of their deprotonation. The complex binds 10 water molecules and forms 22 hydrogen bonds. The large network of hydrogen bonds stabilizes the crystal. The complex has an EPR spectrum both in the solid and in frozen aqueous solution corresponding to mononuclear copper(II). Each copper has a magnetic moment of 1.74 μB. It has two redox processes at 0.62 and 0.79 V (vs SCE), respectively. IR, TG and conproportionation constants were also discussed.

The solid state redox reaction of iron (III) oxalate with sodium nitrate and tin(II) chloride was investigated in hydrogen atmosphere and helium atmosphere by use of a non-isothermal technique. The evolved gases (EG) formed during the reaction were directly detected by gas chromatography, and the solid products were also identified by XRD, Mossbauer spectra and IR. The results show that the solid state redox reaction can go to completion because electron transfer is much easier than mass diffusion along the boundaries of the reactant. The releasing of crystal and coordination water during the redox reaction also facilitates completion of the reaction. The mechanism of the solid state reaction is also discussed.

The thermal decomposition of K 3 Co(CN) 5 L (L = CN − , NO 2 − , N 3 − , NO) in a hydrogen atmosphere has been studied by gas chromatography. The first stage of thermal decomposition of these complexes is to release crystal water if contained, and the second stage is to dissociate the ligand at very high speed, with a large amount of heat being released when LN 3 − . Thirdly, the residual cyano-cobalt complex is further decomposed to form HCN, (CN) 2 and N 2 and a little NH 3 and CH 4 . In the presence of iron powder, the evolution of NH 3 is increased greatly, whereas HCN disappeared entirely. The influence of reduced iron powder upon the decomposition is also studied.