Gd4Ni2BiSi2 crystallizes in the orthorhombic Pnma space group. There are four inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 6-coordinate geometry to one Ni(2), two equivalent Ni(1), one Si(2), two equivalent Si(1), and two equivalent Bi(1) atoms. In the second Gd site, Gd(2) is bonded in a 6-coordinate geometry to one Ni(2), two equivalent Si(1), and three equivalent Bi(1) atoms. In the third Gd site, Gd(3) is bonded in a 8-coordinate geometry to one Ni(1), two equivalent Ni(2), two equivalent Si(1), two equivalent Si(2), and one Bi(1) atom. In the fourth Gd site, Gd(4) is bonded in a 11-coordinate geometry to two equivalent Ni(2), three equivalent Ni(1), one Si(1), three equivalent Si(2), and two equivalent Bi(1) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 10-coordinate geometry to one Gd(3), two equivalent Gd(1), three equivalent Gd(4), three equivalent Si(2), and one Bi(1) atom. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to one Gd(1), one Gd(2), two equivalent Gd(3), two equivalent Gd(4), one Si(2), and two equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Gd(4), two equivalent Gd(1), two equivalent Gd(2), two equivalent Gd(3), and two equivalent Ni(2) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to one Gd(1), two equivalent Gd(3), three equivalent Gd(4), one Ni(2), and three equivalent Ni(1) atoms. Bi(1) is bonded in a 9-coordinate geometry to one Gd(3), two equivalent Gd(1), two equivalent Gd(4), three equivalent Gd(2), and one Ni(1) atom.
Gd4Ni2BiSi2 crystallizes in the orthorhombic Pnma space group. There are four inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 6-coordinate geometry to one Ni(2), two equivalent Ni(1), one Si(2), two equivalent Si(1), and two equivalent Bi(1) atoms. The Gd(1)-Ni(2) bond length is 2.86 Å. Both Gd(1)-Ni(1) bond lengths are 3.38 Å. The Gd(1)-Si(2) bond length is 2.96 Å. Both Gd(1)-Si(1) bond lengths are 2.99 Å. Both Gd(1)-Bi(1) bond lengths are 3.22 Å. In the second Gd site, Gd(2) is bonded in a 6-coordinate geometry to one Ni(2), two equivalent Si(1), and three equivalent Bi(1) atoms. The Gd(2)-Ni(2) bond length is 2.87 Å. Both Gd(2)-Si(1) bond lengths are 2.96 Å. There are two shorter (3.21 Å) and one longer (3.32 Å) Gd(2)-Bi(1) bond length. In the third Gd site, Gd(3) is bonded in a 8-coordinate geometry to one Ni(1), two equivalent Ni(2), two equivalent Si(1), two equivalent Si(2), and one Bi(1) atom. The Gd(3)-Ni(1) bond length is 3.06 Å. Both Gd(3)-Ni(2) bond lengths are 2.96 Å. There is one shorter (2.99 Å) and one longer (3.15 Å) Gd(3)-Si(1) bond length. Both Gd(3)-Si(2) bond lengths are 3.08 Å. The Gd(3)-Bi(1) bond length is 3.56 Å. In the fourth Gd site, Gd(4) is bonded in a 11-coordinate geometry to two equivalent Ni(2), three equivalent Ni(1), one Si(1), three equivalent Si(2), and two equivalent Bi(1) atoms. Both Gd(4)-Ni(2) bond lengths are 2.96 Å. There is one shorter (2.86 Å) and two longer (2.96 Å) Gd(4)-Ni(1) bond lengths. The Gd(4)-Si(1) bond length is 3.00 Å. There are two shorter (3.00 Å) and one longer (3.13 Å) Gd(4)-Si(2) bond length. Both Gd(4)-Bi(1) bond lengths are 3.28 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 10-coordinate geometry to one Gd(3), two equivalent Gd(1), three equivalent Gd(4), three equivalent Si(2), and one Bi(1) atom. There are two shorter (2.37 Å) and one longer (2.60 Å) Ni(1)-Si(2) bond length. The Ni(1)-Bi(1) bond length is 3.12 Å. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to one Gd(1), one Gd(2), two equivalent Gd(3), two equivalent Gd(4), one Si(2), and two equivalent Si(1) atoms. The Ni(2)-Si(2) bond length is 2.40 Å. Both Ni(2)-Si(1) bond lengths are 2.48 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Gd(4), two equivalent Gd(1), two equivalent Gd(2), two equivalent Gd(3), and two equivalent Ni(2) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to one Gd(1), two equivalent Gd(3), three equivalent Gd(4), one Ni(2), and three equivalent Ni(1) atoms. Bi(1) is bonded in a 9-coordinate geometry to one Gd(3), two equivalent Gd(1), two equivalent Gd(4), three equivalent Gd(2), and one Ni(1) atom.