Materials Data on CaMnBi2 by Materials Project
CaMnBi2 is Parent of FeAs superconductors-derived structured and crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ca is bonded to four equivalent Mn and eight Bi atoms to form CaMn4Bi8 cuboctahedra that share corners with four equivalent CaMn4Bi8 cuboctahedra, corners with eight equivalent MnCa4Bi4 tetrahedra, edges with eight equivalent CaMn4Bi8 cuboctahedra, edges with four equivalent MnCa4Bi4 tetrahedra, and faces with four equivalent CaMn4Bi8 cuboctahedra. All Ca–Mn bond lengths are 3.50 Å. There are four shorter (3.41 Å) and four longer (3.46 Å) Ca–Bi bond lengths. Mn is bonded to four equivalent Ca and four equivalent Bi atoms to form distorted MnCa4Bi4 tetrahedra that share corners with eight equivalent CaMn4Bi8 cuboctahedra, edges with four equivalent CaMn4Bi8 cuboctahedra, edges with four equivalent MnCa4Bi4 tetrahedra, and faces with four equivalent MnCa4Bi4 tetrahedra. All Mn–Bi bond lengths are 2.83 Å. There are two inequivalent Bi sites. In the first Bi site, Bi is bonded in a 8-coordinate geometry to four equivalent Ca and four equivalent Mn atoms. In the second Bi site, Bi is bonded in a 8-coordinate geometry to four equivalent Ca and four equivalent Bi atoms. All Bi–Bi bond lengths are 3.26 Å.