Oxidation state VII

Although there are a few examples of iodine bonded only to carbon ligands, most complexes contain other, more electronegative ligands in the coordination sphere. There are few examples of chlorine and bromine complexes, and, as yet, no examples even with iodine of oxidation state VII. Most of these complexes, and especially the more stable examples, have aromatic... 

A series of polyoxotungstate anions which contain high valent rhenium, e.g. [Si-W10Re2O40]2 /3 /4, have been synthesized in the form of Bu"N+ salts.639 The anions contain rhenium in oxidation states VII, VI and V. Cyclic voltammograms, ESR and electronic absorption spectra have been used to characterize these complexes. 

For oxidation state VII there are no complexes other than oxo complexes or the organometallics (e.g., RM03) which are covered in Section 18-D-12. 

By application of strong oxidizing agents, c.g. by melting with alkali peroxides, Np and Pu can be transfonned into the oxidation state VII. 

In the preceding section, the production of manganese chemicals was mentioned. These chemicals refer to the oxidation states up to VI. The preparation of potassium permanganate (oxidation state VII) is performed using electrolysis. 

Rhenium (Re, at. mass 186.21) occurs mainly in oxidation states VII, V, and IV. Rhenium(VIl) compounds are the most stable. The colourless perrhenate, ReOT ion exhibits weak oxidizing properties. The chemical properties of rhenium resemble those of Mo and Mn. Rhenium(V) and (IV) form halide, oxalate, and tartrate complexes. 

In waters, manganese can occur in different oxidation states. In natural waters the oxidation states II, III and IV are of greatest importance. In water treatment, manganese in the oxidation state VII is sometimes used. 

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