Sm4Ni7Si9 crystallizes in the monoclinic C2 space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 17-coordinate geometry to one Ni(3), one Ni(4), one Ni(5), two equivalent Ni(1), three equivalent Ni(2), one Si(3), one Si(4), one Si(5), one Si(6), one Si(7), two equivalent Si(1), and two equivalent Si(2) atoms. In the second Sm site, Sm(2) is bonded in a 17-coordinate geometry to one Ni(3), one Ni(4), one Ni(5), two equivalent Ni(2), three equivalent Ni(1), one Si(3), one Si(4), one Si(5), one Si(6), one Si(7), two equivalent Si(1), and two equivalent Si(2) atoms. There are five inequivalent Ni sites. In the first Ni site, Ni(5) is bonded in a 11-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(4), two equivalent Ni(1), two equivalent Si(2), and two equivalent Si(7) atoms. In the second Ni site, Ni(1) is bonded in a 10-coordinate geometry to two equivalent Sm(1), three equivalent Sm(2), one Ni(5), one Si(1), one Si(3), one Si(4), and one Si(7) atom. In the third Ni site, Ni(2) is bonded in a 9-coordinate geometry to two equivalent Sm(2), three equivalent Sm(1), one Si(2), one Si(3), one Si(4), one Si(5), and one Si(6) atom. In the fourth Ni site, Ni(3) is bonded in a 12-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), two equivalent Ni(4), one Si(6), one Si(7), two equivalent Si(1), and two equivalent Si(2) atoms. In the fifth Ni site, Ni(4) is bonded in a 12-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(5), two equivalent Ni(3), one Si(5), two equivalent Si(1), and two equivalent Si(2) atoms. There are seven inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(1), one Ni(3), one Ni(4), one Si(5), and one Si(6) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(2), one Ni(3), one Ni(4), one Ni(5), and one Si(7) atom. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), two equivalent Ni(1), and two equivalent Ni(2) atoms. In the fourth Si site, Si(4) is bonded in a 8-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), two equivalent Ni(1), and two equivalent Ni(2) atoms. In the fifth Si site, Si(5) is bonded in a 9-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(4), two equivalent Ni(2), and two equivalent Si(1) atoms. In the sixth Si site, Si(6) is bonded in a 9-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(3), two equivalent Ni(2), and two equivalent Si(1) atoms. In the seventh Si site, Si(7) is bonded in a 11-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(3), two equivalent Ni(1), two equivalent Ni(5), and two equivalent Si(2) atoms.
Sm4Ni7Si9 crystallizes in the monoclinic C2 space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 17-coordinate geometry to one Ni(3), one Ni(4), one Ni(5), two equivalent Ni(1), three equivalent Ni(2), one Si(3), one Si(4), one Si(5), one Si(6), one Si(7), two equivalent Si(1), and two equivalent Si(2) atoms. The Sm(1)-Ni(3) bond length is 3.22 Å. The Sm(1)-Ni(4) bond length is 3.30 Å. The Sm(1)-Ni(5) bond length is 3.06 Å. There is one shorter (3.10 Å) and one longer (3.19 Å) Sm(1)-Ni(1) bond length. There are a spread of Sm(1)-Ni(2) bond distances ranging from 3.04-3.39 Å. The Sm(1)-Si(3) bond length is 3.09 Å. The Sm(1)-Si(4) bond length is 3.05 Å. The Sm(1)-Si(5) bond length is 3.11 Å. The Sm(1)-Si(6) bond length is 3.09 Å. The Sm(1)-Si(7) bond length is 3.07 Å. There is one shorter (2.92 Å) and one longer (3.09 Å) Sm(1)-Si(1) bond length. There is one shorter (3.04 Å) and one longer (3.08 Å) Sm(1)-Si(2) bond length. In the second Sm site, Sm(2) is bonded in a 17-coordinate geometry to one Ni(3), one Ni(4), one Ni(5), two equivalent Ni(2), three equivalent Ni(1), one Si(3), one Si(4), one Si(5), one Si(6), one Si(7), two equivalent Si(1), and two equivalent Si(2) atoms. The Sm(2)-Ni(3) bond length is 3.23 Å. The Sm(2)-Ni(4) bond length is 3.18 Å. The Sm(2)-Ni(5) bond length is 3.13 Å. There is one shorter (3.04 Å) and one longer (3.23 Å) Sm(2)-Ni(2) bond length. There are a spread of Sm(2)-Ni(1) bond distances ranging from 3.05-3.32 Å. The Sm(2)-Si(3) bond length is 3.02 Å. The Sm(2)-Si(4) bond length is 3.10 Å. The Sm(2)-Si(5) bond length is 3.12 Å. The Sm(2)-Si(6) bond length is 3.15 Å. The Sm(2)-Si(7) bond length is 3.09 Å. There is one shorter (3.02 Å) and one longer (3.05 Å) Sm(2)-Si(1) bond length. There is one shorter (2.99 Å) and one longer (3.10 Å) Sm(2)-Si(2) bond length. There are five inequivalent Ni sites. In the first Ni site, Ni(5) is bonded in a 11-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(4), two equivalent Ni(1), two equivalent Si(2), and two equivalent Si(7) atoms. The Ni(5)-Ni(4) bond length is 2.69 Å. Both Ni(5)-Ni(1) bond lengths are 2.48 Å. Both Ni(5)-Si(2) bond lengths are 2.30 Å. Both Ni(5)-Si(7) bond lengths are 2.83 Å. In the second Ni site, Ni(1) is bonded in a 10-coordinate geometry to two equivalent Sm(1), three equivalent Sm(2), one Ni(5), one Si(1), one Si(3), one Si(4), and one Si(7) atom. The Ni(1)-Si(1) bond length is 2.28 Å. The Ni(1)-Si(3) bond length is 2.31 Å. The Ni(1)-Si(4) bond length is 2.31 Å. The Ni(1)-Si(7) bond length is 2.33 Å. In the third Ni site, Ni(2) is bonded in a 9-coordinate geometry to two equivalent Sm(2), three equivalent Sm(1), one Si(2), one Si(3), one Si(4), one Si(5), and one Si(6) atom. The Ni(2)-Si(2) bond length is 2.36 Å. The Ni(2)-Si(3) bond length is 2.35 Å. The Ni(2)-Si(4) bond length is 2.33 Å. The Ni(2)-Si(5) bond length is 2.32 Å. The Ni(2)-Si(6) bond length is 2.32 Å. In the fourth Ni site, Ni(3) is bonded in a 12-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), two equivalent Ni(4), one Si(6), one Si(7), two equivalent Si(1), and two equivalent Si(2) atoms. Both Ni(3)-Ni(4) bond lengths are 2.83 Å. The Ni(3)-Si(6) bond length is 2.66 Å. The Ni(3)-Si(7) bond length is 2.73 Å. Both Ni(3)-Si(1) bond lengths are 2.34 Å. Both Ni(3)-Si(2) bond lengths are 2.39 Å. In the fifth Ni site, Ni(4) is bonded in a 12-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(5), two equivalent Ni(3), one Si(5), two equivalent Si(1), and two equivalent Si(2) atoms. The Ni(4)-Si(5) bond length is 2.52 Å. Both Ni(4)-Si(1) bond lengths are 2.32 Å. Both Ni(4)-Si(2) bond lengths are 2.36 Å. There are seven inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(1), one Ni(3), one Ni(4), one Si(5), and one Si(6) atom. The Si(1)-Si(5) bond length is 2.49 Å. The Si(1)-Si(6) bond length is 2.49 Å. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(2), one Ni(3), one Ni(4), one Ni(5), and one Si(7) atom. The Si(2)-Si(7) bond length is 2.45 Å. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), two equivalent Ni(1), and two equivalent Ni(2) atoms. In the fourth Si site, Si(4) is bonded in a 8-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), two equivalent Ni(1), and two equivalent Ni(2) atoms. In the fifth Si site, Si(5) is bonded in a 9-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(4), two equivalent Ni(2), and two equivalent Si(1) atoms. In the sixth Si site, Si(6) is bonded in a 9-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(3), two equivalent Ni(2), and two equivalent Si(1) atoms. In the seventh Si site, Si(7) is bonded in a 11-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), one Ni(3), two equivalent Ni(1), two equivalent Ni(5), and two equivalent Si(2) atoms.