Fei Wang - Revisiting the Zintl-Klemm Concept I: Alkali Metal Trielides

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  Publication Details (including relevant citation   information):

  Fei Wang, and Gordon J. Miller, Inorg. Chem., 2011, 50,   7625-7636.


  To enhance understanding of the Zintl–Klemm concept, which is   useful for characterizing chemical bonding in semimetallic and   semiconducting valence compounds, and to more effectively   rationalize the structures of Zintl phases, we present a   partitioning scheme of the total energy calculated on numerous   possible structures of the alkali metal trielides, LiAl, LiTl,   NaTl, and KTl, using first-principles quantum mechanical   calculations. This assessment of the total energy considers the   relative effects of covalent, ionic, and metallic interactions,   all of which are important to understand the complete structural   behavior of Zintl phases. In particular, valence electron   transfer and anisotropic covalent interactions, explicitly   employed by the Zintl–Klemm concept, are often in competition   with isotropic, volume-dependent metallic and ionic interaction   terms. Furthermore, factors including relativistic effects,   electronegativity differences, and atomic size ratios between the   alkali metal and triel atoms can affect the competition by   enhancing or weakening one of the three energetic contributors   and thus cause structural variations. This partitioning of the   total energy, coupled with analysis of the electronic density of   states curves, correctly predicts and rationalizes the structures   of LiAl, LiTl, NaTl, and KTl, as well as identifies a   pressure-induced phase transition in KTl from its structure,   based on [Tl6]6– distorted octahedra, to   the double diamond NaTl-type.

  Address (URL): http://pubs.acs.org/doi/citedby/10.1021/ic200643f