Anions polyatomic zintl

Polyatomic zintl anions of the post-transition elements. J. D. Corbett, Chem. Rev., 1985, 85, 383 (117). 

Polyatomic Zintl Anions Stabilized Through Crypt Complexation of the Cation... 

Corbett JD (1985) Polyatomic Zintl anions of the post-transition elements. 

The term Zintl phase is applied to solids formed between either an alkali- or alkaline-earth metal and a main group p-block element from group 14, 15, or 16 in the periodic table. These phases are characterized by a network of homonuclear or heteronuclear polyatomic clusters (the Zintl ions), which carry a net negative charge, and that are neutralized by cations. Broader definitions of the Zintl phase are sometimes used. Group 13 elements have been included with the Zintl anions and an electropositive rare-earth element or transition element with a filled d shell (e.g. Cu) or empty d shell (e.g. Ti) has replaced the alkali- or alkaline-earth element in some reports. Although the bonding between the Zintl ions and the cations in the Zintl phases is markedly polar, by our earlier definition those compounds formed between the alkali- or alkaline-earth metals with the heavier anions (i.e. Sn, Pb, Bi) can be considered intermetallic phases. 

Reaction of group 15 elements like arsenic with alkali or alkaline earth metals forms Zintl anions of the general type Asn". Characterization of these species has been accomplished dissolving the solids in liquid NH3 or ethylenediamine (H2NCH2CH2NH2) and adding the macrocycle, 2,2,2-crypt (5) to complex the cations and stabilize the polyatomic anions. The fully characterized Zintl arsenic anions As4, As and Asu are shown inFigme 1. ... 

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