Sm6Ni20As13 crystallizes in the hexagonal P-6 space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 16-coordinate geometry to one Ni(1), one Ni(8), two equivalent Ni(2), two equivalent Ni(5), two equivalent Ni(6), two equivalent Ni(7), two equivalent As(2), and four equivalent As(1) atoms. In the second Sm site, Sm(2) is bonded in a 15-coordinate geometry to one Ni(6), two equivalent Ni(4), two equivalent Ni(5), two equivalent Ni(7), two equivalent Ni(8), two equivalent As(4), and four equivalent As(3) atoms. There are eight inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one Sm(1), one As(4), one As(5), and two equivalent As(2) atoms to form distorted NiSmAs4 tetrahedra that share  a cornercorner with one Ni(5)Sm4As4 tetrahedra, corners with four equivalent Ni(1)SmAs4 tetrahedra,  an edgeedge with one Ni(5)Sm4As4 tetrahedra, edges with two equivalent Ni(7)Sm4As4 tetrahedra, and faces with two equivalent Ni(6)Sm3As4 tetrahedra. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to six equivalent Sm(1) and three equivalent As(1) atoms. In the third Ni site, Ni(3) is bonded in a 5-coordinate geometry to one As(2), two equivalent As(4), and two equivalent As(5) atoms. In the fourth Ni site, Ni(4) is bonded in a distorted trigonal planar geometry to six equivalent Sm(2) and three equivalent As(3) atoms. In the fifth Ni site, Ni(5) is bonded to two equivalent Sm(1), two equivalent Sm(2), one As(3), one As(4), and two equivalent As(1) atoms to form distorted NiSm4As4 tetrahedra that share  a cornercorner with one Ni(1)SmAs4 tetrahedra, corners with two equivalent Ni(6)Sm3As4 tetrahedra, corners with two equivalent Ni(5)Sm4As4 tetrahedra, corners with four equivalent Ni(7)Sm4As4 tetrahedra,  an edgeedge with one Ni(1)SmAs4 tetrahedra, edges with two equivalent Ni(5)Sm4As4 tetrahedra, faces with two equivalent Ni(6)Sm3As4 tetrahedra, and faces with two equivalent Ni(7)Sm4As4 tetrahedra. In the sixth Ni site, Ni(6) is bonded to one Sm(2), two equivalent Sm(1), one As(1), one As(2), and two equivalent As(4) atoms to form distorted NiSm3As4 tetrahedra that share corners with two equivalent Ni(5)Sm4As4 tetrahedra, corners with three equivalent Ni(7)Sm4As4 tetrahedra,  an edgeedge with one Ni(7)Sm4As4 tetrahedra, edges with two equivalent Ni(6)Sm3As4 tetrahedra,  a faceface with one Ni(7)Sm4As4 tetrahedra, faces with two equivalent Ni(5)Sm4As4 tetrahedra, and faces with two equivalent Ni(1)SmAs4 tetrahedra. In the seventh Ni site, Ni(7) is bonded to two equivalent Sm(1), two equivalent Sm(2), one As(1), one As(2), and two equivalent As(3) atoms to form distorted NiSm4As4 tetrahedra that share corners with two equivalent Ni(7)Sm4As4 tetrahedra, corners with three equivalent Ni(6)Sm3As4 tetrahedra, corners with four equivalent Ni(5)Sm4As4 tetrahedra,  an edgeedge with one Ni(6)Sm3As4 tetrahedra, edges with two equivalent Ni(7)Sm4As4 tetrahedra, edges with two equivalent Ni(1)SmAs4 tetrahedra,  a faceface with one Ni(6)Sm3As4 tetrahedra, and faces with two equivalent Ni(5)Sm4As4 tetrahedra. In the eighth Ni site, Ni(8) is bonded in a 4-coordinate geometry to one Sm(1), two equivalent Sm(2), one As(3), one As(4), and two equivalent As(2) atoms. There are five inequivalent As sites. In the first As site, As(3) is bonded in a 9-coordinate geometry to four equivalent Sm(2), one Ni(4), one Ni(5), one Ni(8), and two equivalent Ni(7) atoms. In the second As site, As(4) is bonded in a 9-coordinate geometry to two equivalent Sm(2), one Ni(1), one Ni(5), one Ni(8), two equivalent Ni(3), and two equivalent Ni(6) atoms. In the third As site, As(5) is bonded in a 9-coordinate geometry to three equivalent Ni(1) and six equivalent Ni(3) atoms. In the fourth As site, As(1) is bonded in a 9-coordinate geometry to four equivalent Sm(1), one Ni(2), one Ni(6), one Ni(7), and two equivalent Ni(5) atoms. In the fifth As site, As(2) is bonded in a 9-coordinate geometry to two equivalent Sm(1), one Ni(3), one Ni(6), one Ni(7), two equivalent Ni(1), and two equivalent Ni(8) atoms.
Sm6Ni20As13 crystallizes in the hexagonal P-6 space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 16-coordinate geometry to one Ni(1), one Ni(8), two equivalent Ni(2), two equivalent Ni(5), two equivalent Ni(6), two equivalent Ni(7), two equivalent As(2), and four equivalent As(1) atoms. The Sm(1)-Ni(1) bond length is 3.11 Å. The Sm(1)-Ni(8) bond length is 3.21 Å. Both Sm(1)-Ni(2) bond lengths are 3.04 Å. There is one shorter (3.19 Å) and one longer (3.22 Å) Sm(1)-Ni(5) bond length. Both Sm(1)-Ni(6) bond lengths are 3.18 Å. Both Sm(1)-Ni(7) bond lengths are 3.14 Å. Both Sm(1)-As(2) bond lengths are 3.02 Å. There are two shorter (3.04 Å) and two longer (3.05 Å) Sm(1)-As(1) bond lengths. In the second Sm site, Sm(2) is bonded in a 15-coordinate geometry to one Ni(6), two equivalent Ni(4), two equivalent Ni(5), two equivalent Ni(7), two equivalent Ni(8), two equivalent As(4), and four equivalent As(3) atoms. The Sm(2)-Ni(6) bond length is 3.18 Å. Both Sm(2)-Ni(4) bond lengths are 3.05 Å. Both Sm(2)-Ni(5) bond lengths are 3.15 Å. There is one shorter (3.17 Å) and one longer (3.24 Å) Sm(2)-Ni(7) bond length. Both Sm(2)-Ni(8) bond lengths are 3.08 Å. Both Sm(2)-As(4) bond lengths are 2.96 Å. There are two shorter (3.03 Å) and two longer (3.05 Å) Sm(2)-As(3) bond lengths. There are eight inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one Sm(1), one As(4), one As(5), and two equivalent As(2) atoms to form distorted NiSmAs4 tetrahedra that share  a cornercorner with one Ni(5)Sm4As4 tetrahedra, corners with four equivalent Ni(1)SmAs4 tetrahedra,  an edgeedge with one Ni(5)Sm4As4 tetrahedra, edges with two equivalent Ni(7)Sm4As4 tetrahedra, and faces with two equivalent Ni(6)Sm3As4 tetrahedra. The Ni(1)-As(4) bond length is 2.30 Å. The Ni(1)-As(5) bond length is 2.24 Å. Both Ni(1)-As(2) bond lengths are 2.41 Å. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to six equivalent Sm(1) and three equivalent As(1) atoms. All Ni(2)-As(1) bond lengths are 2.33 Å. In the third Ni site, Ni(3) is bonded in a 5-coordinate geometry to one As(2), two equivalent As(4), and two equivalent As(5) atoms. The Ni(3)-As(2) bond length is 2.39 Å. Both Ni(3)-As(4) bond lengths are 2.73 Å. Both Ni(3)-As(5) bond lengths are 2.55 Å. In the fourth Ni site, Ni(4) is bonded in a distorted trigonal planar geometry to six equivalent Sm(2) and three equivalent As(3) atoms. All Ni(4)-As(3) bond lengths are 2.31 Å. In the fifth Ni site, Ni(5) is bonded to two equivalent Sm(1), two equivalent Sm(2), one As(3), one As(4), and two equivalent As(1) atoms to form distorted NiSm4As4 tetrahedra that share  a cornercorner with one Ni(1)SmAs4 tetrahedra, corners with two equivalent Ni(6)Sm3As4 tetrahedra, corners with two equivalent Ni(5)Sm4As4 tetrahedra, corners with four equivalent Ni(7)Sm4As4 tetrahedra,  an edgeedge with one Ni(1)SmAs4 tetrahedra, edges with two equivalent Ni(5)Sm4As4 tetrahedra, faces with two equivalent Ni(6)Sm3As4 tetrahedra, and faces with two equivalent Ni(7)Sm4As4 tetrahedra. The Ni(5)-As(3) bond length is 2.37 Å. The Ni(5)-As(4) bond length is 2.36 Å. Both Ni(5)-As(1) bond lengths are 2.37 Å. In the sixth Ni site, Ni(6) is bonded to one Sm(2), two equivalent Sm(1), one As(1), one As(2), and two equivalent As(4) atoms to form distorted NiSm3As4 tetrahedra that share corners with two equivalent Ni(5)Sm4As4 tetrahedra, corners with three equivalent Ni(7)Sm4As4 tetrahedra,  an edgeedge with one Ni(7)Sm4As4 tetrahedra, edges with two equivalent Ni(6)Sm3As4 tetrahedra,  a faceface with one Ni(7)Sm4As4 tetrahedra, faces with two equivalent Ni(5)Sm4As4 tetrahedra, and faces with two equivalent Ni(1)SmAs4 tetrahedra. The Ni(6)-As(1) bond length is 2.42 Å. The Ni(6)-As(2) bond length is 2.40 Å. Both Ni(6)-As(4) bond lengths are 2.38 Å. In the seventh Ni site, Ni(7) is bonded to two equivalent Sm(1), two equivalent Sm(2), one As(1), one As(2), and two equivalent As(3) atoms to form distorted NiSm4As4 tetrahedra that share corners with two equivalent Ni(7)Sm4As4 tetrahedra, corners with three equivalent Ni(6)Sm3As4 tetrahedra, corners with four equivalent Ni(5)Sm4As4 tetrahedra,  an edgeedge with one Ni(6)Sm3As4 tetrahedra, edges with two equivalent Ni(7)Sm4As4 tetrahedra, edges with two equivalent Ni(1)SmAs4 tetrahedra,  a faceface with one Ni(6)Sm3As4 tetrahedra, and faces with two equivalent Ni(5)Sm4As4 tetrahedra. The Ni(7)-As(1) bond length is 2.41 Å. The Ni(7)-As(2) bond length is 2.35 Å. Both Ni(7)-As(3) bond lengths are 2.38 Å. In the eighth Ni site, Ni(8) is bonded in a 4-coordinate geometry to one Sm(1), two equivalent Sm(2), one As(3), one As(4), and two equivalent As(2) atoms. The Ni(8)-As(3) bond length is 2.36 Å. The Ni(8)-As(4) bond length is 2.36 Å. Both Ni(8)-As(2) bond lengths are 2.40 Å. There are five inequivalent As sites. In the first As site, As(3) is bonded in a 9-coordinate geometry to four equivalent Sm(2), one Ni(4), one Ni(5), one Ni(8), and two equivalent Ni(7) atoms. In the second As site, As(4) is bonded in a 9-coordinate geometry to two equivalent Sm(2), one Ni(1), one Ni(5), one Ni(8), two equivalent Ni(3), and two equivalent Ni(6) atoms. In the third As site, As(5) is bonded in a 9-coordinate geometry to three equivalent Ni(1) and six equivalent Ni(3) atoms. In the fourth As site, As(1) is bonded in a 9-coordinate geometry to four equivalent Sm(1), one Ni(2), one Ni(6), one Ni(7), and two equivalent Ni(5) atoms. In the fifth As site, As(2) is bonded in a 9-coordinate geometry to two equivalent Sm(1), one Ni(3), one Ni(6), one Ni(7), two equivalent Ni(1), and two equivalent Ni(8) atoms.