Binding energies (BE) of 18 pure vanadium compounds (V 2p3/2 niveau) were measured in selected oxygen and chlorine environments, linearity of BE vs. oxidation states scrutinized and appropriate model compounds chosen as comparative standards. The general trend is an increase of BE with formal oxidation state; in particular, it could be counterbalanced by electron donating/withdrawing ligands on the V atom. A graphical (computerized) background substraction method was utilized to remove an interfering O 1s satellite peak and to enhance accuracy of BE values in surface compounds. BEs of (SiO)3VO (I), (SiO)3V (II), and (SiO)3V(O2) (III) were determined. By comparison to standards positive BE shifts of about 2.1 eV were derived indicating the strong electron withdrawing (“electron sink”) effect of the support on V in surface compounds. This is the first reported ESCA data on a surface peroxo complex, (III). Some implications of the results are also discussed.

Mn[N(SiMe3)2]2(THF) (I) (Me = methyl, THF = tetrahydrofuran) was obtained on large scale from “active” MnCl2 and LiN(SiMe3)2 in THE in 85–93% yield. The novel, theoretically interesting tetra‐coordinated Mn[N(SiMe3)2]2L2 series was derived from I, where L = THF, pyridine and t‐butyleyanide. All these species are quite stable thermally and exhibit exteme oxygen sensitivity. Preparation, properties, and reactions of unsymmetrically substituted (“hemi”) XMnY type compounds are presented also, where X = Cl, NO3 and n = butyl, and Y = N(SiMe3)2 and OR. From ClMnN(SiMe3)2, with or without coordinated THF being present, the unusual (Mn{SiMe3)2, was isolated as yellow crystals. The “hemi” Mn(II)‐system exhibits only moderate thermal stability and tends to disproportionate. Many derivatives are photosensitive, especially with UV light.

A series of novel, air sensitive alkoxides of Mn(II) were prepared by alcoholysis reaction of Mn{N(SiMe3)2}2 · (THF), including sterically highly hindered derivatives soluble in organic solvents. The products, characterized by elemental analysis, reflectance spectroscopy and chemical behavior, range from amorphous coordination polymers and gelatinous fibers to (probably monomeric) crystals. Earlier literature descriptions of several Mn(II) alkoxides is corrected. Some oxidation results are discussed.

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Novel, generally highly oxygen sensitive („hemi”︁) ClCrN(SiMe3)2(L)n, I, and Cr[N(SiMe3)2]2LL′, II, were prepared with L, L′ = (a) aliphatic and cyclic ethers (including polyfunctional ligands) (b) alkyl cyanides, (c) aromatic tertiary amines or (d) mixtures of a and c. The products are characterized by elemental analysis and chemical reactions. Representative reflectance spectra are presented. Chemical and physical properties are strongly dependent on the nature of L, L′ and oxygen sensitivity, thermal stability, solubility and reactivity of the CrN linkage (in reactions with surface ) could be regulated by varying the coordinated ligands. Empirical reactivity series for various LL′ combinations and ligand lability interrelationships were established. Behavior of some complexes in Cr(II) alkoxide synthesis, ring opening polymerizations, and in pyrolysis reactions is discussed.