Materials Data on Sr3Sc2Cu2S2O5 by Materials Project

Sr3Sc2O5(CuS)2 crystallizes in the tetragonal I4/mmm space group. The structure is two-dimensional and consists of two CuS sheets oriented in the (0, 0, 1) direction and two Sr3Sc2O5 sheets oriented in the (0, 0, 1) direction. In each CuS sheet, Cu1+ is bonded to four equivalent S2- atoms to form a mixture of edge and corner-sharing CuS4 tetrahedra. All Cu–S bond lengths are 2.44 Å. S2- is bonded in a 9-coordinate geometry to four equivalent Cu1+ atoms. In each Sr3Sc2O5 sheet, there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with four equivalent SrO12 cuboctahedra, faces with four equivalent SrO12 cuboctahedra, and faces with eight equivalent ScO5 square pyramids. There are four shorter (2.90 Å) and eight longer (3.06 Å) Sr–O bond lengths. In the second Sr2+ site, Sr2+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All Sr–O bond lengths are 2.55 Å. Sc3+ is bonded to five O2- atoms to form ScO5 square pyramids that share corners with five equivalent ScO5 square pyramids and faces with four equivalent SrO12 cuboctahedra. There are one shorter (2.00 Å) and four longer (2.07 Å) Sc–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four equivalent Sr2+ and two equivalent Sc3+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to four Sr2+ and two equivalent Sc3+ atoms.