Materials Data on Ca4Bi2O by Materials Project
Ca4Bi2O is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to five equivalent Bi and one O atom to form a mixture of distorted edge and corner-sharing CaBi5O octahedra. The corner-sharing octahedra tilt angles range from 0–13°. There are one shorter (3.26 Å) and four longer (3.39 Å) Ca–Bi bond lengths. The Ca–O bond length is 2.74 Å. In the second Ca site, Ca is bonded in a linear geometry to four equivalent Bi and two equivalent O atoms. All Ca–Bi bond lengths are 3.34 Å. Both Ca–O bond lengths are 2.38 Å. Bi is bonded in a 9-coordinate geometry to nine Ca atoms. O is bonded to six Ca atoms to form corner-sharing OCa6 octahedra. The corner-sharing octahedral tilt angles are 0°.