Sm4CuSn8 crystallizes in the orthorhombic Pmm2 space group. There are four inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 10-coordinate geometry to two equivalent Sn(1), two equivalent Sn(3), two equivalent Sn(6), and four equivalent Sn(7) atoms. In the second Sm site, Sm(2) is bonded in a 10-coordinate geometry to two equivalent Sn(2), two equivalent Sn(4), two equivalent Sn(5), and four equivalent Sn(8) atoms. In the third Sm site, Sm(3) is bonded in a 14-coordinate geometry to four equivalent Cu(1), two equivalent Sn(1), two equivalent Sn(3), two equivalent Sn(8), and four equivalent Sn(5) atoms. In the fourth Sm site, Sm(4) is bonded in a 10-coordinate geometry to two equivalent Sn(2), two equivalent Sn(4), two equivalent Sn(7), and four equivalent Sn(6) atoms. Cu(1) is bonded in a 9-coordinate geometry to four equivalent Sm(3), one Sn(5), two equivalent Sn(1), and two equivalent Sn(3) atoms. There are eight inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 10-coordinate geometry to two equivalent Sm(1), two equivalent Sm(3), two equivalent Cu(1), and four equivalent Sn(3) atoms. In the second Sn site, Sn(2) is bonded in a 8-coordinate geometry to two equivalent Sm(2), two equivalent Sm(4), and four equivalent Sn(4) atoms. In the third Sn site, Sn(3) is bonded in a 10-coordinate geometry to two equivalent Sm(1), two equivalent Sm(3), two equivalent Cu(1), and four equivalent Sn(1) atoms. In the fourth Sn site, Sn(4) is bonded in a 8-coordinate geometry to two equivalent Sm(2), two equivalent Sm(4), and four equivalent Sn(2) atoms. In the fifth Sn site, Sn(5) is bonded in a 9-coordinate geometry to two equivalent Sm(2), four equivalent Sm(3), one Cu(1), and two equivalent Sn(8) atoms. In the sixth Sn site, Sn(6) is bonded in a 8-coordinate geometry to two equivalent Sm(1), four equivalent Sm(4), and two equivalent Sn(7) atoms. In the seventh Sn site, Sn(7) is bonded in a 8-coordinate geometry to two equivalent Sm(4), four equivalent Sm(1), and two equivalent Sn(6) atoms. In the eighth Sn site, Sn(8) is bonded in a 8-coordinate geometry to two equivalent Sm(3), four equivalent Sm(2), and two equivalent Sn(5) atoms.
Sm4CuSn8 crystallizes in the orthorhombic Pmm2 space group. There are four inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 10-coordinate geometry to two equivalent Sn(1), two equivalent Sn(3), two equivalent Sn(6), and four equivalent Sn(7) atoms. Both Sm(1)-Sn(1) bond lengths are 3.34 Å. Both Sm(1)-Sn(3) bond lengths are 3.31 Å. Both Sm(1)-Sn(6) bond lengths are 3.59 Å. All Sm(1)-Sn(7) bond lengths are 3.23 Å. In the second Sm site, Sm(2) is bonded in a 10-coordinate geometry to two equivalent Sn(2), two equivalent Sn(4), two equivalent Sn(5), and four equivalent Sn(8) atoms. Both Sm(2)-Sn(2) bond lengths are 3.31 Å. Both Sm(2)-Sn(4) bond lengths are 3.38 Å. Both Sm(2)-Sn(5) bond lengths are 3.37 Å. All Sm(2)-Sn(8) bond lengths are 3.18 Å. In the third Sm site, Sm(3) is bonded in a 14-coordinate geometry to four equivalent Cu(1), two equivalent Sn(1), two equivalent Sn(3), two equivalent Sn(8), and four equivalent Sn(5) atoms. All Sm(3)-Cu(1) bond lengths are 3.38 Å. Both Sm(3)-Sn(1) bond lengths are 3.52 Å. Both Sm(3)-Sn(3) bond lengths are 3.55 Å. Both Sm(3)-Sn(8) bond lengths are 3.79 Å. All Sm(3)-Sn(5) bond lengths are 3.33 Å. In the fourth Sm site, Sm(4) is bonded in a 10-coordinate geometry to two equivalent Sn(2), two equivalent Sn(4), two equivalent Sn(7), and four equivalent Sn(6) atoms. Both Sm(4)-Sn(2) bond lengths are 3.37 Å. Both Sm(4)-Sn(4) bond lengths are 3.31 Å. Both Sm(4)-Sn(7) bond lengths are 3.46 Å. All Sm(4)-Sn(6) bond lengths are 3.19 Å. Cu(1) is bonded in a 9-coordinate geometry to four equivalent Sm(3), one Sn(5), two equivalent Sn(1), and two equivalent Sn(3) atoms. The Cu(1)-Sn(5) bond length is 2.49 Å. Both Cu(1)-Sn(1) bond lengths are 2.65 Å. Both Cu(1)-Sn(3) bond lengths are 2.63 Å. There are eight inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 10-coordinate geometry to two equivalent Sm(1), two equivalent Sm(3), two equivalent Cu(1), and four equivalent Sn(3) atoms. All Sn(1)-Sn(3) bond lengths are 3.12 Å. In the second Sn site, Sn(2) is bonded in a 8-coordinate geometry to two equivalent Sm(2), two equivalent Sm(4), and four equivalent Sn(4) atoms. All Sn(2)-Sn(4) bond lengths are 3.12 Å. In the third Sn site, Sn(3) is bonded in a 10-coordinate geometry to two equivalent Sm(1), two equivalent Sm(3), two equivalent Cu(1), and four equivalent Sn(1) atoms. In the fourth Sn site, Sn(4) is bonded in a 8-coordinate geometry to two equivalent Sm(2), two equivalent Sm(4), and four equivalent Sn(2) atoms. In the fifth Sn site, Sn(5) is bonded in a 9-coordinate geometry to two equivalent Sm(2), four equivalent Sm(3), one Cu(1), and two equivalent Sn(8) atoms. Both Sn(5)-Sn(8) bond lengths are 2.89 Å. In the sixth Sn site, Sn(6) is bonded in a 8-coordinate geometry to two equivalent Sm(1), four equivalent Sm(4), and two equivalent Sn(7) atoms. Both Sn(6)-Sn(7) bond lengths are 2.94 Å. In the seventh Sn site, Sn(7) is bonded in a 8-coordinate geometry to two equivalent Sm(4), four equivalent Sm(1), and two equivalent Sn(6) atoms. In the eighth Sn site, Sn(8) is bonded in a 8-coordinate geometry to two equivalent Sm(3), four equivalent Sm(2), and two equivalent Sn(5) atoms.