Unfamiliar oxidation states and their stabilization

Abstract

Unfamiliar oxidation states have been characterized principally by four types of evidence: (1) analytical data and chemical properties; (2) isomorphism with compounds containing atoms of known oxidation state; (3) 0>-CH-N^> (C) ,0H HO * Swann and Xanthakos (J. Am. Soc, 53, 400 [1931]) have been able to obtain cobalt(III) sulfate by the anodic oxidation of cobalt(II) sulfate in 10 N sulfuric acid. INTRODUCTION *5 The products of the thermal decomposition of the triiodide and bromide of samarium at 800-900 0 in a high vacuum are the dihalides and the corresponding free halogens. 43 Halides of dipositive ytterbium are prepared in a similar manner. 44 * Oxidation numbers as low as 1.9 have recently been obtained (Mazzitelli, M.S. thesis. University of Kansas, 1949). * The reducing power of the solution after electrolysis was determined by titration with iodine. * These data are taken from an article by Tsentnershver and Blumenthal, Bull, intern, acad. polonaise, classe sci. math, nat., 1933A, pp. 499-522. There is some disagreement with the earlier values for the melting points of Rb0 2 and Cs0 2 (see ref. 2c). Similar values for the heats of formation of the superoxides are given by de Forcrand, Compt. rend., 158, 991 (1914). * Yost, Russell, and Garner, The Rare Earth Elements and Their Compounds, p. 9.

Chelate Complexes of 1,10-Phenanthroline and Related Compounds.

“…However, it might be mentioned that the sparingly soluble chromium(I1) salt addenda with hydrazine are also quite stable in the solid state. This can be ascribed to either their insolubility or the reducing power of the hydrazine molecule (163,278). The magnetic moment of the bromide (3.27 B.M.)…”

Identification of Gaseous Cobalt Tetrafluoride: MS and FTIR Spectroscopic Studies

“…The existence of compounds with unusual valence states is of considerable scientific interest, because the achievement of unusual states of oxidation is connected to the theories of chemical valence and bonding. The theoretical and experimental aspects of this problem were discussed in the 1950s . However, the synthesis and the investigation of compounds at the limits of thermodynamic stability are difficult to carry out without obtaining unambiguous results.…”

Unfamiliar oxidation states, 1952-54

“…The electropositive character of iodine and bromine is sufficiently great that the unipositive ions of these elements are capable of existence. These ions may be stabilized by coordination with such nitrogen bases as pyridine (21). Recent work apparently has demonstrated that iodine(I) can exist to a limited extent in solutions of molecular iodine in water and ethanol.…”