Metal perhalates, halates and halites

It is convenient to classify here the decompositions of metal salts of the various oxyhalogen acids on the basis of the oxygen content of the anion, with subsections devoted to the metals of a particular sub-group of the Periodic Table. Again, consideration of the ammonium salts is deferred to Sect. 4. As noted elsewhere in this review, some reports are not explicit as to whether or not melting accompanies reaction thermal analysis studies can be valuable [843]. 

A comprehensive and detailed review of the literature relating to the decomposition reactions of the salts of halogen oxyacids has recently been given by Solymosi [1279], This book discusses many aspects of the chemical characteristics of this group of compounds. It includes a large amount of kinetic data and provides access to the original publications. 

An important source of reference is another excellent review by Stern [844] this one is concerned with the high temperature properties of oxy-halides. The following general trends are found in salts containing an XO anion (X = Cl, Br and I) there are variations in stabilities in the sequences (i) (X =) Cl Br I for halogens in the same oxidation state, and (ii) XO4 XOJ XO2 XCT for the different oxidation states of a particular halogen. 

Decomposition often proceeds by the stepwise release of oxygen, viz. 

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