Metal mixed suboxides

The chemically different behavior of Rb and Cs is demonstrated in the structures of the Rb—Cs mixed suboxides. It is interesting to learn about the chemical similarity, too, by investigating, whether a mutual exchange of these metals is possible. Experiments have led to initial answers to the questions, which of the clusters, Rb902 or CS11O3, is the more stable one and what the conditions are to substitute the metal atoms specifically in the clusters and in the oxygen-free parts of the structures. 

When Rb-Cs alloys of appropriate composition are partially oxidized, then the two metals which are so much alike in their aqueous chemistry exhibit an entirely different behavior. They beeome spatially separated in the suboxides, whereby the Cs enters into [Csn03] clusters and the Rb is distributed in the purely metallic regions between the elusters. Examples are Csu03Rb (n = 7, 2, 1). [4] There is evidence for the existence of K-Cs mixed suboxides that should, according to what has been said about the Rb-Cs suboxides, have the general comporition Cs,03K or Cs,i03(Cs, K) . Unfortunately, they decompose at 215 K under K2O deposition so that only preliminary X-ray and thermal analysis data have been obtained to identify their existence. 

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