Zintl phase

Zintl phases are intermetallic compounds between electropositive alkali metals or alkaline earth metals and moderately electronegative elements from the 11th to the 16th group of the periodic table. Your name was suggested in honor Zintls by Eduard Zintls death of Fritz Laves and quickly accepted.

In these compounds, the electron, formally attributed to the more electronegative element according to Eduard Zintl and Wilhelm Klemm. The structured anion sublattice corresponds according to E. Busmann and Wilhelm Klemm which an element tree of the same valence electron. The Zintl border or line can be drawn 13 to 14 group, it separates the salt-like phases of the alloy-type phases of the 11 to 13 group.

For example, the structure of the thallium Anionenteilgitters in Natriumthallid ( NaTl ) the face-centered cubic lattice, with half of the tetrahedral holes is again occupied by Tl atoms. The sodium cations sit in the other half of the tetrahedral sites and octahedral sites in the crystal lattice. Another of many examples is sodium silicide ( NaSi ), in analogy to the white phosphorus Si44 - forms tetrahedron.

Many Zintl phases, due to the partially covalent partially ionic bonds with resultant relatively small bandgap (<1 eV) diamagnetic semiconductor, whose conductivity increases in contrast to the metallic conductors with increasing temperature.