Zintl ion

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] 

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RESULTS AND DISCUSSION Structure factors and stability of Zintl ions... 

T. Fassler, S. D. Hoffmann, Endohedral Zintl ions intermetallic clusters. Angew. Chem. Int. Ed. 43 (2004) 6242. 

In an effort to make the distannyne, Ar Sn=SnAr (Ar = 2,6-(2,4,6-Pr 3C6H2)2C6H3), Ar SnH was heated in toluene hydrogen was eliminated but SnC bonds also were cleaved, and gave the paramagnetic cluster Ar 3Sn9 59 (g= ca. 2.031), with a structure that is based on the 21-electron [Sng]3- cage that is known as a Zintl ion.478... 

A large number of nine-vertex Zintl ions are known (see details in the next section). Those having electron counts of 32 + 8 = 40 (Eg4-, E = Si, Ge, Sn, Pb), do... 

A comprehensive book on chemistry, structure and bonding of Zintl compounds has been edited by Kauzlarich (1996) in this book several aspects of Zintl phases such as structural patterns, molecular transition complexes of Zintl ions, transition metal Zintl compounds are deeply discussed. 

In a review, Van der Lugt (1996) observed that a number of liquid alloys (K-Pb, Rb-Pb, Cs-Pb, K-Sn, Rb-Sn, Cs-Sn, K-Te) behave as if all the anions were in the form of perfect simple Zintl anions like tetrahedra and dumbbells this being suggested by the behaviour of many physical properties (resistivity, thermodynamic properties, etc.) as a composition function. In this context a simple Zintl ion was defined as a polyanion that assumes the same configuration as a neutral isoelec-tronic element. A similar definition was reported by Van der Lugt and Verkerk... 

Zintl ions are polyanions formed by anion clustering in ionic alloys. Two categories were considered those that fit the so-called Zintl-Klemm concept and those that are electron-deficient. 

Structure and Bonding in Zintl Ions and Related Main Group Element Clusters... 

Abstract This chapter reviews the methods that are useful for understanding the structure and bonding in Zintl ions and related bare post-transition element clusters in approximate historical order. After briefly discussing the Zintl-Klemm model the Wade-Mingos rules and related ideas are discussed. The chapter concludes with a discussion of the jellium model and special methods pertaining to bare metal clusters with interstitial atoms. 

Keywords Jellium model Metal clusters Wade-Mingos rules Zintl ions Contents... 

The Relationship of Zintl Ions to Polyhedral Boranes The Wade-Mingos... 

Early Efforts to Rationalize the Structures of the Zintl Ions The Zintl-Klemm Concept... 

Early efforts to rationalize the observed formulas and chemical bonding of Zintl ions and related species used initially the Zintl-Klemm concept [10, 11] and subsequently the Mooser-Pearson [12] extended (8 — AO rule. In this rule, refers... 

The efforts to rationalize the formulas and structures of Zintl ions and related species predated extensive definitive structural information on anionic post-transition metal clusters obtained by Corbett and his group in the 1970s [8, 9]. After enough such structural information on the bare post-transition metal clusters became available, the resemblance of their polyhedra to the known polyhedral boranes became apparent. For this reason, the simple Zintl-Klemm concept has been largely superseded by newer, more advanced descriptions of chemical bonding in such clusters, initially those applied to the polyhedral boranes. 

The next development in the understanding of structure and bonding in the Zintl ions recognized their relationship to the polyhedral boranes and the isoelectronic carboranes. Then the Wade-Mingos rules [13-16], which were developed to understand the structure and bonding in polyhedral boranes, could be extended to isovalent Zintl ions and related post-transition element clusters. 

Fig. 3 Examples of the shapes of some Zintl ions and related clusters...

Abstract A complete review of the NMR, EPR, general spectroscopic properties, and the dynamic behavior of the group 14 Zintl ions and their derivatives are provided. The review focuses primarily on the and Sn NMR studies... 

Transition Metal Derivatives of the Group 14 Zintl Ions. 69... 

This review will focus on the NMR properties of Zintl ion complexes, namely the solution properties of the ions where E = Si, Ge, Sn, Pb, and the products derived from those clusters. Closely related clusters prepared by other means, such as the recent, elegant organo polystannane work of Schnepf, Power, Huttner, and Fischer, are briefly mentioned but are not the focus of this review. Related overviews of dynamic organometallic complexes [1,2] and the stmcture and bonding of Zintl ions [3-5] can be found in previous reviews and in other chapters of this book. 

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