Ca3Os is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to four equivalent Ca(2) and four equivalent Os(1) atoms to form a mixture of distorted edge, corner, and face-sharing CaCa4Os4 tetrahedra. In the second Ca site, Ca(2) is bonded in a 14-coordinate geometry to eight equivalent Ca(1) and six equivalent Os(1) atoms. Os(1) is bonded in a distorted body-centered cubic geometry to six equivalent Ca(2) and eight equivalent Ca(1) atoms.
Ca3Os is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to four equivalent Ca(2) and four equivalent Os(1) atoms to form a mixture of distorted edge, corner, and face-sharing CaCa4Os4 tetrahedra. All Ca(1)-Ca(2) bond lengths are 3.19 Å. All Ca(1)-Os(1) bond lengths are 3.19 Å. In the second Ca site, Ca(2) is bonded in a 14-coordinate geometry to eight equivalent Ca(1) and six equivalent Os(1) atoms. All Ca(2)-Os(1) bond lengths are 3.69 Å. Os(1) is bonded in a distorted body-centered cubic geometry to six equivalent Ca(2) and eight equivalent Ca(1) atoms.