U2Tc3Si5 crystallizes in the tetragonal P4/mnc space group. U(1) is bonded in a 11-coordinate geometry to two equivalent Tc(1), two equivalent Tc(2), two equivalent Si(1), three equivalent Si(3), and four equivalent Si(2) atoms. There are two inequivalent Tc sites. In the first Tc site, Tc(1) is bonded in a 8-coordinate geometry to two equivalent U(1), two equivalent Si(1), two equivalent Si(2), and two equivalent Si(3) atoms. In the second Tc site, Tc(2) is bonded to four equivalent U(1), two equivalent Tc(2), two equivalent Si(2), and four equivalent Si(3) atoms to form a mixture of distorted face and corner-sharing TcU4Si6Tc2 cuboctahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to four equivalent U(1), four equivalent Tc(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 11-coordinate geometry to four equivalent U(1), one Tc(2), two equivalent Tc(1), two equivalent Si(2), and two equivalent Si(3) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to three equivalent U(1), two equivalent Tc(1), two equivalent Tc(2), and two equivalent Si(2) atoms.
U2Tc3Si5 crystallizes in the tetragonal P4/mnc space group. U(1) is bonded in a 11-coordinate geometry to two equivalent Tc(1), two equivalent Tc(2), two equivalent Si(1), three equivalent Si(3), and four equivalent Si(2) atoms. Both U(1)-Tc(1) bond lengths are 3.09 Å. Both U(1)-Tc(2) bond lengths are 3.30 Å. Both U(1)-Si(1) bond lengths are 2.99 Å. There is one shorter (2.89 Å) and two longer (2.93 Å) U(1)-Si(3) bond lengths. There are two shorter (3.15 Å) and two longer (3.19 Å) U(1)-Si(2) bond lengths. There are two inequivalent Tc sites. In the first Tc site, Tc(1) is bonded in a 8-coordinate geometry to two equivalent U(1), two equivalent Si(1), two equivalent Si(2), and two equivalent Si(3) atoms. Both Tc(1)-Si(1) bond lengths are 2.53 Å. Both Tc(1)-Si(2) bond lengths are 2.49 Å. There is one shorter (2.46 Å) and one longer (2.50 Å) Tc(1)-Si(3) bond length. In the second Tc site, Tc(2) is bonded to four equivalent U(1), two equivalent Tc(2), two equivalent Si(2), and four equivalent Si(3) atoms to form a mixture of distorted face and corner-sharing TcU4Si6Tc2 cuboctahedra. Both Tc(2)-Tc(2) bond lengths are 2.74 Å. Both Tc(2)-Si(2) bond lengths are 2.69 Å. All Tc(2)-Si(3) bond lengths are 2.45 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to four equivalent U(1), four equivalent Tc(1), and one Si(1) atom. The Si(1)-Si(1) bond length is 2.57 Å. In the second Si site, Si(2) is bonded in a 11-coordinate geometry to four equivalent U(1), one Tc(2), two equivalent Tc(1), two equivalent Si(2), and two equivalent Si(3) atoms. Both Si(2)-Si(2) bond lengths are 2.74 Å. Both Si(2)-Si(3) bond lengths are 2.57 Å. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to three equivalent U(1), two equivalent Tc(1), two equivalent Tc(2), and two equivalent Si(2) atoms.