Materials Data on KCdAs by Materials Project
KCdAs is Matlockite structured and crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. K1+ is bonded to five equivalent As3- atoms to form distorted KAs5 trigonal bipyramids that share corners with twelve equivalent CdAs4 tetrahedra, corners with four equivalent KAs5 trigonal bipyramids, edges with four equivalent CdAs4 tetrahedra, and edges with eight equivalent KAs5 trigonal bipyramids. There are four shorter (3.47 Å) and one longer (3.56 Å) K–As bond lengths. Cd2+ is bonded to four equivalent As3- atoms to form CdAs4 tetrahedra that share corners with four equivalent CdAs4 tetrahedra, corners with twelve equivalent KAs5 trigonal bipyramids, edges with four equivalent CdAs4 tetrahedra, and edges with four equivalent KAs5 trigonal bipyramids. All Cd–As bond lengths are 2.85 Å. As3- is bonded in a 9-coordinate geometry to five equivalent K1+ and four equivalent Cd2+ atoms.