Polyatomic Cations of Other Elements

We have not discussed the evidence for polyatomic cations formed in the mass spectrometer or as transient reaction intermediates instead we have concentrated on recent work on those polyatomic cations that exist as stable entities in solution or in the solid state. We may add that evidence has also been given for the formation of Pba + 14 7), Mga 148), Caa 149), Sra 150), and Bag 150) on addition of the respective element to the corresponding MCla melt at high temperatures, and ESR evidence has been presented for Ag or Ag4 151), Aga, Cd. 

Salts of homopolyatomic cationic clusters now constitute a well-established class of compound— there are at least twenty-six fairly well-characterized examples. It is probable that many other elements will also be shown to form polyatomic cations. As yet reactions of these species have been little studied, and there is obviously a wide open field here awaiting exploration. Many structures of known cations, as well as those that have not yet been prepared, remain to be investigated, and there is a need for theories that can predict the stability and geometry of these cations and provide a description of the bonding. 

Herzberg, G., Molecular Spectra and Molecular Structure, Vol. I. Van Nostrand-Reinhold, Princeton, New Jersey, 1960. 

Siebert, H., Anwendungen der Schwingungs spektroskopie in der Anor-ganischen Chemie. Springer-Verlag, Berlin and New York, 1966. 

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