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A systematic investigation of the systems MNbS and MTaS (M = Mn, Fe, Co, Ni) revealed the presence of the compounds MNb3S6 and MTa36. Their structures were determined from powder diagrams. They proved to have a superstructure, derived from the 2s−NbS2 type and resulting from an ordered distribution of the metal atoms M over the octahedral holes between the prismatic NbS2 layers. The magnetic susceptibilities were measured; all the compounds showed a temperature-dependent paramagnetism with a spontaneous localized moment.

The abnormally low value of the magnetic susceptibility of Co 3 O 4 and ZnCo 2 O 4 and the uncertainty about the valence of the cobalt ions in these spinels has led to the investigation of mixed crystals of CoO and ZnO . The magnetic susceptibility of the ( Co , Zn ) O mixed crystals, measured up to 1200°K, could be represented by ζ = α + C T − θ with a fairly large temperature-independent paramagnetism (α = 0.5 × 10 −3 e.m.u.) and a magnetic moment for the Co 2 + ions in tetrahedral interstices of 4.05 μ β . The susceptibility measurements on several samples of ZnCo 2 O 4 indicated that Co 3 + ions are present in the octahedral holes. They showed only a small temperature-independent paramagnetism of 0.1 × 10 −3 e.m.u. It appears that in this spinel tervalent cobalt behaves in a similar way as in the numerous six-coordinated complex compounds. The temperature dependence of the molar susceptibility of Co 3 O 4 : ζ m = α + C T − θ with α = 0.7 × 10 −3 e.m.u. and μ = 4.14μ β is now easily explained on the assumption that this compound is a normal 2–3 spinel. The tervalent cobalt ions in the octahedral interstices do not exhibit a permanent moment, which explains the low susceptibility values. The Co 3 + ions in the octahedral of the perowskite LaCoO 3 seem to be normally paramagnetic. This difference in behaviour of tervalent cobalt in the octahedra of various oxygen lattices and the behaviour of divalent cobalt in tetrahedra can be qualitatively understood with the aid of the ⪡crystal field⪢ theory.

It is shown that in π-allylpalladium complexes, e.g. (π-C4H7)PdClL (L = AsPh3, PPh3) and substituted π-methallyl compounds, so called “πσ” reactions may occur, i.e. reversible interconversions from the π-allyl to a short-lived σ-allyl form with interchange of the syn- and anti-protons. These interchanges are caused either by reactions of the monomeric complex with excess free ligand L or by reactions of the complex with dimeric π-allylpalladium chloride compounds. In the case of these dimer-dependent “πσ” reactions it was found that at low temperatures syn- and anti-protons interchange on one side of the allyl group, whereas at higher temperatures interchange occurs on both sides of the allyl group of the monometer. The interchange on one side was studied in particular for various phosphine compounds. It proved to be first order in the monomer and first order in the dimer complex for L =P(n-C4H9)3. Additional information about “πσ” reactions in general was further obtained for dimethyl-substituted π-methallylpalladium compounds. Also included are the results of NMR measurements on the formation and ligand exchange reactions of ionic complexes [(π-C4H7)Pd(PR3)2]+Cl− for various phosphines.