The crystal structure of Cd3As2
Abstract
<h2>Acta Crystallographica Section B</h2><h3>Structural Crystallography and Crystal Chemistry</h3><h3>0567-7408</h3> <h2>research papers</h2> Volume 24 Part 8 Pages 1062-1067 August 1968 <h2>The crystal structure of Cd 3 As 2 </h2> G. A. Steigmann and J. Goodyear Acta Cryst. (1968). B24, 1062 The Crystal Structure of Cd3As2 BY G.A. STEIGMANN AND J. GOODYEAR Physics Department, The University of Hull, England (Received 20 September 1967) A Weissenberg study of the structure of Cd3As2 has shown that the unit cell is tetragonal (a= 12.67 + 0.01/~, c=25"48+ 0.02 A, Z= 32, space group I41cd). Arsenic ions are approximately cubic close- packed and Cd ions are tetrahedrally coordinated. The main difference between the present structure and that proposed by von Stackelberg & Paulus lies in the disposition of the vacant tetrahedral sites. Both structures are geometrically related to the fluorite structure. Introduction The crystal structure of Cd3As2 was determined by yon Stackelberg & Paulus (1935) as tetragonal (a= 8.95, c= 12.65 A, space group P42/nmc) with As ions approximately in a cubic close-packed array. Cd ions were tetrahedrally coordinated and each As ion was surrounded by Cd ions at six of the eight corners of a distorted cube, the two vacant sites being at diagonally