CuMn3As2 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to two equivalent Cu(1), one As(2), and three equivalent As(1) atoms. In the second Mn site, Mn(2) is bonded in a 5-coordinate geometry to three equivalent Cu(1), two equivalent As(2), and three equivalent As(1) atoms. In the third Mn site, Mn(3) is bonded in a 5-coordinate geometry to one Cu(1), two equivalent As(1), and three equivalent As(2) atoms. Cu(1) is bonded to one Mn(3), two equivalent Mn(1), three equivalent Mn(2), two equivalent Cu(1), one As(1), and three equivalent As(2) atoms to form distorted face-sharing CuMn6Cu2As4 cuboctahedra. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 9-coordinate geometry to two equivalent Mn(3), three equivalent Mn(1), three equivalent Mn(2), and one Cu(1) atom. In the second As site, As(2) is bonded in a 9-coordinate geometry to one Mn(1), two equivalent Mn(2), three equivalent Mn(3), and three equivalent Cu(1) atoms.
CuMn3As2 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to two equivalent Cu(1), one As(2), and three equivalent As(1) atoms. Both Mn(1)-Cu(1) bond lengths are 2.61 Å. The Mn(1)-As(2) bond length is 2.51 Å. There is one shorter (2.35 Å) and two longer (2.40 Å) Mn(1)-As(1) bond lengths. In the second Mn site, Mn(2) is bonded in a 5-coordinate geometry to three equivalent Cu(1), two equivalent As(2), and three equivalent As(1) atoms. There are two shorter (2.85 Å) and one longer (2.87 Å) Mn(2)-Cu(1) bond length. Both Mn(2)-As(2) bond lengths are 2.66 Å. There is one shorter (2.51 Å) and two longer (2.62 Å) Mn(2)-As(1) bond lengths. In the third Mn site, Mn(3) is bonded in a 5-coordinate geometry to one Cu(1), two equivalent As(1), and three equivalent As(2) atoms. The Mn(3)-Cu(1) bond length is 2.89 Å. Both Mn(3)-As(1) bond lengths are 2.54 Å. There is one shorter (2.42 Å) and two longer (2.57 Å) Mn(3)-As(2) bond lengths. Cu(1) is bonded to one Mn(3), two equivalent Mn(1), three equivalent Mn(2), two equivalent Cu(1), one As(1), and three equivalent As(2) atoms to form distorted face-sharing CuMn6Cu2As4 cuboctahedra. Both Cu(1)-Cu(1) bond lengths are 2.48 Å. The Cu(1)-As(1) bond length is 2.50 Å. There are two shorter (2.49 Å) and one longer (2.55 Å) Cu(1)-As(2) bond length. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 9-coordinate geometry to two equivalent Mn(3), three equivalent Mn(1), three equivalent Mn(2), and one Cu(1) atom. In the second As site, As(2) is bonded in a 9-coordinate geometry to one Mn(1), two equivalent Mn(2), three equivalent Mn(3), and three equivalent Cu(1) atoms.