Exploring New Zintl Phases in the 9-4-9 Family via Al Substitution. Synthesis, Structure, and Physical Properties of AeMnAlSb (Ae = Ca, Yb, Eu).

Three new quaternary Zintl phases with the "9-4-9" formula, AeMnAlSb (Ae = Ca, Yb, Eu), have been synthesized using Pb as the metal flux, and their crystal structures have been established by single-crystal X-ray diffraction. Both CaMnAlSb and YbMnAlSb are isostructural with CaMnBi, and they crystallize in the orthorhombic space group with unit cell dimensions of = 12.4571(8), 12.

Sr14Sn3As12 and Eu14Sn3As12: enantiomorph-like Zintl compounds.

Two new chiral Zintl compounds, Sr14Sn3As12 and Eu14Sn3As12, were synthesized from tin-flux reactions, and the structures were determined by using single-crystal X-ray diffraction. Both compounds crystallize in the trigonal space group R3 (No. 146, Z = 3) with the anion structures containing various units: dumbbell-shaped [Sn2As6](12-) dimers, [SnAs3](7-) triangular pyramids, and isolated As(3-) anions.

Crystal structure of Ba5In4Sb6.

The title compound, penta-barium tetra-indium hexa-anti-mony, was synthesized by an indium-flux reaction and its structure features layers composed of edge-sharing In2Sb6 units. The voids between the In4Sb6 layers are filled by Ba(2+) cations, which are all surrounded by six Sb atoms and form bicapped octa-hedral or triangular prismatic coordination geometries. There are five barium ions in the asymmetric unit: one has no imposed crystallographic symmetry, two lie on mirror planes and two have mm2 point symmetry.

Synthesis, structure and bonding, optical properties of Ba₄MTrQ₆ (M=Cu, Ag; Tr=Ga, In; Q=S, Se).

Four new quaternary chalcogenides, Ba4AgGaS6 (1), Ba4AgGaSe6 (2), Ba4CuInS6 (3), and Ba4AgInS6 (4), were synthesized by solid-state reactions and their structures were characterized through single-crystal X-ray diffraction. In spite of their similar chemical compositions, the flexible arrangement between the transition metals and the triel atoms leads to subtle differences in their polyanion structures. All structures feature similar [MTrQ6](8-) 1D polyanionic chains (M=Cu, Ag; Tr=Ga, In; Q=S, Se), which are constructed from corner-sharing MQ4 or TrQ4 tetrahedra.

Ba13Si6Sn8As22: a quaternary Zintl phase containing adamantane-like [Si4As10] clusters.

A new quaternary arsenide Zintl phase, Ba13Si6Sn8As22, has been synthesized from the Sn-flux reactions, and the structure was determined by the single-crystal X-ray diffraction methods. The compound crystallizes in the tetragonal non-centrosymmetric space group I42m (No. 121) with unit cell parameters of a = b = 14.

Synthesis, crystal and electronic structures, and properties of the new pnictide semiconductors A2CdPn2 (A = Ca, Sr, Ba, Eu; Pn = P, As).

A series of ternary Zintl phases, Ca(2)CdP(2), Ca(2)CdAs(2), Sr(2)CdAs(2), Ba(2)CdAs(2), and Eu(2)CdAs(2), have been synthesized through high temperature metal flux reactions, and their structures have been characterized by single-crystal X-ray diffraction. They belong to the Yb(2)CdSb(2) structure type and crystallize in the orthorhombic space group Cmc2(1) (No. 36, Z = 4) with cell dimensions of a = 4.