Sc3Co2Si3 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded in a 9-coordinate geometry to four equivalent Co(1), two equivalent Si(2), and three equivalent Si(1) atoms. In the second Sc site, Sc(2) is bonded in a 10-coordinate geometry to four equivalent Co(1), two equivalent Si(1), and four equivalent Si(2) atoms. Co(1) is bonded in a 10-coordinate geometry to two equivalent Sc(1), four equivalent Sc(2), one Si(1), and three equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to three equivalent Sc(1), four equivalent Sc(2), and two equivalent Co(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Sc(1), four equivalent Sc(2), three equivalent Co(1), and one Si(2) atom.
Sc3Co2Si3 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded in a 9-coordinate geometry to four equivalent Co(1), two equivalent Si(2), and three equivalent Si(1) atoms. All Sc(1)-Co(1) bond lengths are 2.99 Å. Both Sc(1)-Si(2) bond lengths are 2.69 Å. There are two shorter (2.74 Å) and one longer (3.05 Å) Sc(1)-Si(1) bond length. In the second Sc site, Sc(2) is bonded in a 10-coordinate geometry to four equivalent Co(1), two equivalent Si(1), and four equivalent Si(2) atoms. There are three shorter (2.85 Å) and one longer (2.96 Å) Sc(2)-Co(1) bond length. Both Sc(2)-Si(1) bond lengths are 2.76 Å. There are two shorter (2.80 Å) and two longer (2.90 Å) Sc(2)-Si(2) bond lengths. Co(1) is bonded in a 10-coordinate geometry to two equivalent Sc(1), four equivalent Sc(2), one Si(1), and three equivalent Si(2) atoms. The Co(1)-Si(1) bond length is 2.45 Å. There are two shorter (2.27 Å) and one longer (2.33 Å) Co(1)-Si(2) bond length. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to three equivalent Sc(1), four equivalent Sc(2), and two equivalent Co(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Sc(1), four equivalent Sc(2), three equivalent Co(1), and one Si(2) atom. The Si(2)-Si(2) bond length is 2.49 Å.