Neue ternäre Alkaliphosphide mit Kupfer, Zink und Cadmium: K2CuP, NaZnP und K4CdP2 / On New Ternary Alkali Metal Phosphides: K2CuP, NaZnP and K4CdP2

Abstract

The new compounds K2CuP, NaZnP and K4CdP2 have been prepared and structurally charac­terized. The crystallographic data are: K2CuP: orthorhombic, space group Cmcm (No. 63). Na2CuAs structure type with a = 983.9(5) pm. b = 739.7(4) pm, c = 579.5(3) pm. There are CuP2- zigzag chains, which are isosteric to the chains in HgO. NaZnP: tetragonal, space group P4/nmm (No. 129). PbFCl structure type with a = 406.6(2) pm. c = 689.3(3) pm, c/a = 1.695. K4CdP2: monoclinic, space group C2/m (No. 12). New structure type with a = 984.0(5) pm, b = 568.1(3) pm. c = 957.5(5) pm. β = 110.0(1)°. There are discrete [P−Cu−P]4- anions, which are isosteric to the HgCl2 molecules.