Ca5Sn3 crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent Sn(2) and three equivalent Sn(1) atoms to form a mixture of distorted corner, face, and edge-sharing CaSn5 trigonal bipyramids. In the second Ca site, Ca(2) is bonded in a square co-planar geometry to four equivalent Sn(1) atoms. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 9-coordinate geometry to two equivalent Ca(2), six equivalent Ca(1), and one Sn(1) atom. In the second Sn site, Sn(2) is bonded in a 8-coordinate geometry to eight equivalent Ca(1) atoms.
Ca5Sn3 crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent Sn(2) and three equivalent Sn(1) atoms to form a mixture of distorted corner, face, and edge-sharing CaSn5 trigonal bipyramids. Both Ca(1)-Sn(2) bond lengths are 3.45 Å. There is one shorter (3.16 Å) and two longer (3.31 Å) Ca(1)-Sn(1) bond lengths. In the second Ca site, Ca(2) is bonded in a square co-planar geometry to four equivalent Sn(1) atoms. All Ca(2)-Sn(1) bond lengths are 3.22 Å. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 9-coordinate geometry to two equivalent Ca(2), six equivalent Ca(1), and one Sn(1) atom. The Sn(1)-Sn(1) bond length is 2.87 Å. In the second Sn site, Sn(2) is bonded in a 8-coordinate geometry to eight equivalent Ca(1) atoms.