CeOsSi3 crystallizes in the tetragonal I4mm space group. Ce(1) is bonded in a 17-coordinate geometry to five equivalent Os(1), four equivalent Si(1), and eight equivalent Si(2) atoms. Os(1) is bonded in a 5-coordinate geometry to five equivalent Ce(1), one Si(1), and four 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 four equivalent Ce(1), one Os(1), and four equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a distorted bent 120 degrees geometry to four equivalent Ce(1), two equivalent Os(1), and two equivalent Si(1) atoms.
CeOsSi3 crystallizes in the tetragonal I4mm space group. Ce(1) is bonded in a 17-coordinate geometry to five equivalent Os(1), four equivalent Si(1), and eight equivalent Si(2) atoms. All Ce(1)-Os(1) bond lengths are 3.39 Å. All Ce(1)-Si(1) bond lengths are 3.07 Å. There are four shorter (3.13 Å) and four longer (3.41 Å) Ce(1)-Si(2) bond lengths. Os(1) is bonded in a 5-coordinate geometry to five equivalent Ce(1), one Si(1), and four equivalent Si(2) atoms. The Os(1)-Si(1) bond length is 2.34 Å. All Os(1)-Si(2) bond lengths are 2.37 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to four equivalent Ce(1), one Os(1), and four equivalent Si(2) atoms. All Si(1)-Si(2) bond lengths are 2.63 Å. In the second Si site, Si(2) is bonded in a distorted bent 120 degrees geometry to four equivalent Ce(1), two equivalent Os(1), and two equivalent Si(1) atoms.