Materials Data on La(AlGe)2 by Materials Project

Abstract

LaAl2Ge2 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. La is bonded to six equivalent Ge atoms to form distorted LaGe6 octahedra that share corners with twelve equivalent AlGe4 tetrahedra, edges with six equivalent LaGe6 octahedra, and edges with six equivalent AlGe4 tetrahedra. All La–Ge bond lengths are 3.14 Å. Al is bonded to four equivalent Ge atoms to form distorted AlGe4 tetrahedra that share corners with six equivalent LaGe6 octahedra, corners with six equivalent AlGe4 tetrahedra, edges with three equivalent LaGe6 octahedra, and edges with three equivalent AlGe4 tetrahedra. The corner-sharing octahedra tilt angles range from 23–53°. All Al–Ge bond lengths are 2.58 Å. Ge is bonded to three equivalent La and four equivalent Al atoms to form a mixture of distorted corner and edge-sharing GeLa3Al4 pentagonal bipyramids.