Zintl concept

The structures of both Eu3lnP3 and Eu3ln2P4 can be understood within the Zintl concept, as has been described for the alkaline earth analogs [27-29]. In... 

In this review, we present a selection of studies from our own laboratory, intended to introduce a solid-state chemist to both the practical and theoretical considerations that need to be taken into account in XPS measurements of solids with substantial covalent character. Metal phosphides, arsenides, and antimonides represent such a category of solids where the bonding retains some polarity that notions of electron counting derived from the Zintl concept still prove helpful in providing a frame of reference for comparing charge distributions. We also describe the applications of XAS to complementary studies of the electronic structure of these materials. 

In the cationic systems, the positive charges are delocalized over almost all atoms, even if the individual structures may be described by the Zintl concept that assigns localized positive charges to tricoordinate E atoms. It appears that the Zintl concept is better suited, yet not sufficient, to describe the structures of the heavier chalcogen elements. 

At a first glance the above mentioned electron transfer would require the application of the Zintl concept (designated in a later version as the Zintl-Klemm-Busmann concept [10]) as a tool for understanding the structural properties of alkali and alkaline earth amalgams. In simple words the Zintl concept says that the... 

Which, of course, brings me to the exception—the marvelous and useful Zintl concept.3 The simple notion, introduced by Zintl and popularized by Klemm, Busmann, Herbert Schafer, and others, is that in some compounds AxBy, where A is very electropositive relative to a main group element B, one could just think, that s all, think that the A atoms transfer their electrons to the B atoms, which then use them to form bonds. This very simple idea, in my opinion, is the single most important theoretical concept (and how not very theoretical it is ) in solid state chemistry of this century. And it is important not just because it explains so much chemistry, but because it forges a link between solid state chemistry and organic, or main group, chemistry. 

The steady, gradual variation of the P-P distance would seem to be as inconsistent with the molecular orbital model shown here as it was with the Zintl concept. This is not so. If we turn on the interaction between the P atoms and the metal layer (and we have seen before that this interaction is substantial), we will get a mixing of P and Mn orbitals. The discontinuity of the above picture (either single-bond or no bond) will be replaced by a continuous variation of P o and o orbitals occupation between 2 and 0. 

Table 2 Examples of binary compounds obeying the Zintl concept...

The Zintl concept has been extended to include transition metal compounds, with some Although... 

Further examples of formally subvalent main group compounds that contain element-element bonds but not necessarily clusters are the Zintl phases. The bonding in these has been described as the octet rule for all atoms . The archetypal Zintl compound is NaTl, in which charges are assigned as Na+ and Tl, representing a formal transfer of electrons from the more to the less electropositive element. The Tl ion can be considered to be a group 14 pseudoelement, and in fact exists in NaTl as a three-dimensional polyanionic diamond framework (TN) stuffed with Na+ cations. The Zintl concept is extended more broadly to other binary and ternary solid-state compounds, whose structures show the formation of element-element bonds in one, two, or three dimensions. ... 

Zintl concept, 3, 57 Zone edge, zone center, 9... 

The Zintl concept has been extended to include transition metal compounds, with some success.Although many main group metal Zintl compounds are known, there are relatively few examples of isostructural transition... 

Chemical Bonding From the Zintl Concept to the Electron-Localizahilily Approach... 

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