Oxides non-stoichiometric

Oxide, non-stoichiometric approx compn, Tb407, for this formula Tb3+ and Tb + are present in equal amounts. Dark brown Or black solid obtained by igniting the oxalate or the sulfate. Dissolves in hot coned acids with formation of salts loses oxygen on heating forms the oxide when heated in hydrogen. 

Wet chemical analysis of the composition of PAM has evidenced that the content of Pb02 in the active material is always less than 95%. Lead dioxide has been found to contain a certain amount of low-valency Pb and Pb ions. This makes the oxide non-stoichiometric, PbO(2- ). Various values for x have been cited in the literature. Table 12.1 presents some of these values for PAM obtained at different temperatures [16]. 

The nickel hexa-aza-macrocyclic complex (9) may be oxidized non-stoichiometrically by iodine producing a black powder. This material demonstrates spectroscopic features anticipated for a partially oxidized nickel complex. 

Up to temperatures of about 600°C Ae reaction is not complete and Ae presence of small amounts of crystalline V2O5 togeAer wiA VSbOa is detected by X-ray diffraction (XRD) analysis m Ae sample wiA a V Sb=1.0 ratio (Fig. la). When excess antimony is present (Sb V=3.0), ciystalline V2O5 is not detected by XRD analysis which shows Ae presence of only VSb04 and a-Sb204 (Fig. b). TTie values observed for Ae rutile phase correspond to Aose attributed by Berry et al. [6a] to VSb1.yO4.2y (oxidized non-stoichiometric vanadium-an-timonate). 

---

See also in sourсe #XX -- [ ]

---