Reinvestigation of Na₃P based on single-crystal data

The structure of tris­odium phosphide, Na₃P, known from X-ray powder diffraction data, has been refined based on single-crystal data. The compound crystallizes in the hexa­gonal A₃B (A = alkali metal and B = group 15 element) structure type and is isotypic with the homologous potassium phase. The framework is built of Na⁺ and P^3- ions arranged in two kinds of layers perpendicular to the c axis. Two of the Na atoms and the P atom reside at positions of m2 (2b), 3m (4f) and m2 (2c) site symmetry, respectively.

Reinvestigation of MnSn₂

The structure of manganese distannite, MnSn₂, known from X-ray powder diffraction data, has been refined based on single-crystal data. This inter­metallic compound crystallizes in the tetra­gonal CuAl₂ structure type. Mn atoms (4a position) form chains parallel to the c axis and each Mn atom is surrounded by eight Sn atoms in a square anti­prism. Each Sn atom (8h position) has four Mn near neighbors from two neighboring Mn chains forming Mn₄Sn recta­ngular prisms.