Überblick über die Phosphide des Strontiums

The method of the reaction in a stainless steel cube which was used for the first time in the preparation of barium phosphides is also applicable to phosphide-producing mixtures of strontium and phosphorus. In connection with high temperature experiments it served to obtain a survey of the binary system strontium—phosphorus. This binary system is largely analogous to the binary system barium—phosphorus. The compounds found were: “Sr₂P”, Sr₃P₂, Sr₄P₃? Sr_1,1P, SrP, Sr₄P₅ and SrP². The strontium-rich phosphides have melting or decomposing temperatures which are higher than those of the analogous barium phosphides. The powders of Sr₃P₂, Sr₄P₃ and SrP are brown to blackviolet. Sr₃P₂ cristallizes isostructurally with Ba₃P₂. Some properties indicate that the bonding is more ionic than in Ba₃P₂. The structural relationship of the alkaline earth pnietides with the lanthanide chalogenides is discussed. Sr₃P₂ and Ba₃P₂ complete the inverse isostructures of these compounds.     

Ein neues Oxozincat: Über KNaZnO2

A New Oxozincate: On KNaZnO₂ For the first time, KNaZnO₂ has been prepared by heating a mixture of “Na₂ZnO₂” and K₂ZnO₂ in the ratio Na:K = 1:1 [Ag-cylinders, sealed under Argon in Supermax amp. 500–600°C, 7–14 d: powder] as well as of the binary compounds KO_0.54, Na₂O and ZnO in the ratio K:Na:Zn = 1.1:1.1:1 [powder in the same way; single crystals at 700°C, 14 d]. The powder is colourless, the prism shaped single crystals are transparent and colourless. The structure determination [619 symmetry independent hkl, four-circle-diffraktometer Philips PW 1100, ω–2Θ-scan, MoKα, R = 9.20% and R_w = 9.51%, absorption not considered] proves the space group P2₁/c with a = 5.824(1), b = 9.700(2), c = 5.513(1) Å, β = 103.73(1)°, Z = 4, d_x = 3.50, d_pyk = 3.36 g · cm^?3. Parameters see text. The constructional relations of the structure are deduced from Extended Schlegel Diagrams. The Madelung Part of Lattice Energy, MAPLE, effective coordination numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated and discussed.