ZnSnAs2 is beta beryllia-derived structured and crystallizes in the trigonal R3m space group. Zn(1) is bonded to one As(2) and three equivalent As(1) atoms to form ZnAs4 tetrahedra that share corners with six equivalent Zn(1)As4 tetrahedra and corners with six equivalent Sn(1)As4 tetrahedra. Sn(1) is bonded to one As(1) and three equivalent As(2) atoms to form SnAs4 tetrahedra that share corners with six equivalent Zn(1)As4 tetrahedra and corners with six equivalent Sn(1)As4 tetrahedra. There are two inequivalent As sites. In the first As site, As(1) is bonded to three equivalent Zn(1) and one Sn(1) atom to form distorted AsZn3Sn tetrahedra that share corners with six equivalent As(1)Zn3Sn tetrahedra and corners with six equivalent As(2)ZnSn3 tetrahedra. In the second As site, As(2) is bonded to one Zn(1) and three equivalent Sn(1) atoms to form AsZnSn3 tetrahedra that share corners with six equivalent As(1)Zn3Sn tetrahedra and corners with six equivalent As(2)ZnSn3 tetrahedra.
ZnSnAs2 is beta beryllia-derived structured and crystallizes in the trigonal R3m space group. Zn(1) is bonded to one As(2) and three equivalent As(1) atoms to form ZnAs4 tetrahedra that share corners with six equivalent Zn(1)As4 tetrahedra and corners with six equivalent Sn(1)As4 tetrahedra. The Zn(1)-As(2) bond length is 2.61 Å. All Zn(1)-As(1) bond lengths are 2.47 Å. Sn(1) is bonded to one As(1) and three equivalent As(2) atoms to form SnAs4 tetrahedra that share corners with six equivalent Zn(1)As4 tetrahedra and corners with six equivalent Sn(1)As4 tetrahedra. The Sn(1)-As(1) bond length is 2.60 Å. All Sn(1)-As(2) bond lengths are 2.70 Å. There are two inequivalent As sites. In the first As site, As(1) is bonded to three equivalent Zn(1) and one Sn(1) atom to form distorted AsZn3Sn tetrahedra that share corners with six equivalent As(1)Zn3Sn tetrahedra and corners with six equivalent As(2)ZnSn3 tetrahedra. In the second As site, As(2) is bonded to one Zn(1) and three equivalent Sn(1) atoms to form AsZnSn3 tetrahedra that share corners with six equivalent As(1)Zn3Sn tetrahedra and corners with six equivalent As(2)ZnSn3 tetrahedra.