Zintl ions synthesis

Deltahedral Zintl Ions of Tin Synthesis, Structure, and Reactivity... 

Negatively charged clusters of some of the p-metals and semimetals are also stable in solutions and can be crystallized from them as ionic molecular compounds. Known, at present, are a number of such ligand-free anionic clusters, called Zintl ions. Some examples are the clusters with general formulas PUy", Eg , Eg , aud Ej where Pn = P, As, Sb and E = Si, Ge, Sn, Pb. This chapter will limit its attention to the synthesis, structure, and functionalization of molecular anionic clusters of tin. Although both nine- and five-atom clusters are known (Figure 2.6.1), the focus will be predominantly on the nine-atom deltahedral clusters Sug and Sn which are the most readily prepared and most extensively studied species. 

A further development in the synthesis of Zintl ions has been to use the reactions of an excess of Sn or Pb in solutions of Li in liquid NH3. These reactions give [Li(NH3)4] salts of [Sng]" and [Pbg]", and we discuss these Zintl ions further in Section 13.7. 

There is a close relationship between the solution-based syntheses of the naked clusters, as described above, and pure solid state chemistry. This relationship stems from the fact that homonuclear bonding and discrete clusters in many cases also exist within alloys of the type used in the synthesis of Zintl ions in solution. Indeed, such alloys are often to be regarded as well-defined intermetallic compounds. ... 

This chapter reviews the synthesis, structures and physical properties of homoatomic Zintl ions and recent developments in the formation of mixed clusters consisting of the tetrel elements Ge, Sn, and Pb and various d-block elements. A brief summary is provided of the chemistry of homoatomic clusters (this has been reviewed earlier [1,2]), with the main focus being oriented towards the latest results in the field of intermetalloid clusters [3, 4]... 

The bottom-up synthesis of well-defined (semi)metal and intermetalloid clusters that can reach the nanometer scale represents a major challenge. Deltahedral structures reach a limit in size unless more capable templates are found. However, Zintl ions themselves can serve as building units for the formation of larger structures, including classical and nonclassical tetrel-tetrel bonds. Two further examples justify the plan to use such tetrel dusters as precursors for nanoscale dusters ... 

Garcia, E., A.H. Cowley and A.J. Bard. Quaternary ammonium amalgams as Zintl ion salts and their use in the synthesis of novel quaternary ammonium salts. J. Am. Chem. Soc. 108 (1986) 6082. 

Adolphson, D. G., J. D. Corbett, and D. J. Merryman. Stable homopolyatomic anions of the post-transition metals. Zintl ions . The synthesis and structure of a salt containing the heptantimonide(3-) anion. J. Am. Chem. Soc. 98 (1976) 7234. 

O Connor, C.J., Jung, J.-S. and Zhang, J.H. (1996) Synthesis and characterization of intermetallic materials using Zintl phases as precursors. In Chemistry, Structure and Bonding ofZintl Phases and Ions, ed. Kauzlarich, S.M. (VCH Publication, New York), p. 275. 

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