Materials Data on Ba2CaCu2MoO8 by Materials Project
Ba2CaMoCu2O8 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ba2+ is bonded in a 12-coordinate geometry to eight O2- atoms. There are four shorter (2.80 Å) and four longer (2.88 Å) Ba–O bond lengths. Ca2+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Ca–O bond lengths are 2.51 Å. Mo6+ is bonded to six O2- atoms to form corner-sharing MoO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There is two shorter (1.91 Å) and four longer (1.97 Å) Mo–O bond length. Cu2+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.97 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Ba2+, two equivalent Ca2+, and two equivalent Cu2+ atoms to form a mixture of distorted face, edge, and corner-sharing OBa2Ca2Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–67°. In the second O2- site, O2- is bonded in a linear geometry to two equivalent Mo6+ atoms. In the third O2- site, O2- is bonded in a distorted single-bond geometry to four equivalent Ba2+ and one Mo6+ atom.