MgAs crystallizes in the trigonal R32 space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent As(1) and four equivalent As(2) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to six equivalent Mg(1) atoms to form distorted corner-sharing AsMg6 pentagonal pyramids. In the second As site, As(2) is bonded in a 7-coordinate geometry to six equivalent Mg(1) and one As(2) atom.
MgAs crystallizes in the trigonal R32 space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent As(1) and four equivalent As(2) atoms. Both Mg(1)-As(1) bond lengths are 2.71 Å. There are two shorter (2.85 Å) and two longer (2.89 Å) Mg(1)-As(2) bond lengths. There are two inequivalent As sites. In the first As site, As(1) is bonded to six equivalent Mg(1) atoms to form distorted corner-sharing AsMg6 pentagonal pyramids. In the second As site, As(2) is bonded in a 7-coordinate geometry to six equivalent Mg(1) and one As(2) atom. The As(2)-As(2) bond length is 2.54 Å.