Tb2Os3Si5 is Magnesium tetraboride-derived structured and crystallizes in the tetragonal P4/mnc space group. Tb(1) is bonded in a 13-coordinate geometry to two equivalent Os(1), two equivalent Os(2), two equivalent Si(1), three equivalent Si(2), and four equivalent Si(3) atoms. There are two inequivalent Os sites. In the first Os site, Os(1) is bonded in a 6-coordinate geometry to two equivalent Tb(1), two equivalent Si(1), two equivalent Si(2), and two equivalent Si(3) atoms. In the second Os site, Os(2) is bonded in a 6-coordinate geometry to four equivalent Tb(1), two equivalent Si(3), and four equivalent Si(2) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to four equivalent Tb(1) and four equivalent Os(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to three equivalent Tb(1), two equivalent Os(1), two equivalent Os(2), and two equivalent Si(3) atoms. In the third Si site, Si(3) is bonded in a 11-coordinate geometry to four equivalent Tb(1), one Os(2), two equivalent Os(1), two equivalent Si(2), and two equivalent Si(3) atoms.
Tb2Os3Si5 is Magnesium tetraboride-derived structured and crystallizes in the tetragonal P4/mnc space group. Tb(1) is bonded in a 13-coordinate geometry to two equivalent Os(1), two equivalent Os(2), two equivalent Si(1), three equivalent Si(2), and four equivalent Si(3) atoms. Both Tb(1)-Os(1) bond lengths are 3.18 Å. Both Tb(1)-Os(2) bond lengths are 3.26 Å. Both Tb(1)-Si(1) bond lengths are 3.02 Å. There is one shorter (2.81 Å) and two longer (3.03 Å) Tb(1)-Si(2) bond lengths. There are two shorter (3.13 Å) and two longer (3.16 Å) Tb(1)-Si(3) bond lengths. There are two inequivalent Os sites. In the first Os site, Os(1) is bonded in a 6-coordinate geometry to two equivalent Tb(1), two equivalent Si(1), two equivalent Si(2), and two equivalent Si(3) atoms. Both Os(1)-Si(1) bond lengths are 2.48 Å. There is one shorter (2.45 Å) and one longer (2.47 Å) Os(1)-Si(2) bond length. Both Os(1)-Si(3) bond lengths are 2.45 Å. In the second Os site, Os(2) is bonded in a 6-coordinate geometry to four equivalent Tb(1), two equivalent Si(3), and four equivalent Si(2) atoms. Both Os(2)-Si(3) bond lengths are 2.61 Å. All Os(2)-Si(2) bond lengths are 2.40 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to four equivalent Tb(1) and four equivalent Os(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to three equivalent Tb(1), two equivalent Os(1), two equivalent Os(2), and two equivalent Si(3) atoms. Both Si(2)-Si(3) bond lengths are 2.55 Å. In the third Si site, Si(3) is bonded in a 11-coordinate geometry to four equivalent Tb(1), one Os(2), two equivalent Os(1), two equivalent Si(2), and two equivalent Si(3) atoms. Both Si(3)-Si(3) bond lengths are 2.84 Å.