Sr(MgAs)2 crystallizes in the trigonal P-3m1 space group. Sr(1) is bonded to six equivalent As(1) atoms to form SrAs6 octahedra that share corners with twelve equivalent Mg(1)As4 tetrahedra, edges with six equivalent Sr(1)As6 octahedra, and edges with six equivalent Mg(1)As4 tetrahedra. Mg(1) is bonded to four equivalent As(1) atoms to form MgAs4 tetrahedra that share corners with six equivalent Sr(1)As6 octahedra, corners with six equivalent Mg(1)As4 tetrahedra, edges with three equivalent Sr(1)As6 octahedra, and edges with three equivalent Mg(1)As4 tetrahedra. The corner-sharing octahedral tilt angles range from 20-53°. As(1) is bonded to three equivalent Sr(1) and four equivalent Mg(1) atoms to form a mixture of distorted edge and corner-sharing AsSr3Mg4 pentagonal bipyramids.
Sr(MgAs)2 crystallizes in the trigonal P-3m1 space group. Sr(1) is bonded to six equivalent As(1) atoms to form SrAs6 octahedra that share corners with twelve equivalent Mg(1)As4 tetrahedra, edges with six equivalent Sr(1)As6 octahedra, and edges with six equivalent Mg(1)As4 tetrahedra. All Sr(1)-As(1) bond lengths are 3.21 Å. Mg(1) is bonded to four equivalent As(1) atoms to form MgAs4 tetrahedra that share corners with six equivalent Sr(1)As6 octahedra, corners with six equivalent Mg(1)As4 tetrahedra, edges with three equivalent Sr(1)As6 octahedra, and edges with three equivalent Mg(1)As4 tetrahedra. The corner-sharing octahedral tilt angles range from 20-53°. There are three shorter (2.67 Å) and one longer (2.72 Å) Mg(1)-As(1) bond length. As(1) is bonded to three equivalent Sr(1) and four equivalent Mg(1) atoms to form a mixture of distorted edge and corner-sharing AsSr3Mg4 pentagonal bipyramids.