Materials Data on NaCdAs by Materials Project
NaCdAs crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Na1+ is bonded to five equivalent As3- atoms to form distorted NaAs5 trigonal bipyramids that share corners with eight equivalent CdAs4 tetrahedra, corners with eight equivalent NaAs5 trigonal bipyramids, edges with six equivalent CdAs4 tetrahedra, and edges with six equivalent NaAs5 trigonal bipyramids. There are a spread of Na–As bond distances ranging from 3.05–3.27 Å. Cd2+ is bonded to four equivalent As3- atoms to form CdAs4 tetrahedra that share corners with eight equivalent CdAs4 tetrahedra, corners with eight equivalent NaAs5 trigonal bipyramids, edges with two equivalent CdAs4 tetrahedra, and edges with six equivalent NaAs5 trigonal bipyramids. There are three shorter (2.77 Å) and one longer (2.86 Å) Cd–As bond lengths. As3- is bonded in a 9-coordinate geometry to five equivalent Na1+ and four equivalent Cd2+ atoms.