Materials Data on Ca9Mn4Bi9 by Materials Project

Abstract

Ca9Mn4Bi9 is Magnesium tetraboride-derived structured and crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are five inequivalent Ca sites. In the first Ca site, Ca is bonded in a 6-coordinate geometry to two equivalent Mn and six Bi atoms. Both Ca–Mn bond lengths are 3.66 Å. There are two shorter (3.33 Å) and four longer (3.44 Å) Ca–Bi bond lengths. In the second Ca site, Ca is bonded to six Bi atoms to form a mixture of distorted edge and corner-sharing CaBi6 octahedra. The corner-sharing octahedral tilt angles are 44°. There are a spread of Ca–Bi bond distances ranging from 3.27–3.45 Å. In the third Ca site, Ca is bonded in a 8-coordinate geometry to two Mn and six Bi atoms. There are one shorter (3.33 Å) and one longer (3.74 Å) Ca–Mn bond lengths. There are a spread of Ca–Bi bond distances ranging from 3.26–3.58 Å. In the fourth Ca site, Ca is bonded in a 8-coordinate geometry to two equivalent Mn and six Bi atoms. Both Ca–Mn bond lengths are 3.28 Å. There are a spread of Ca–Bi bond distances ranging from 3.23–3.74 Å. In the fifth Ca site, Ca is bonded in a 5-coordinate geometry to four Mn and five Bi atoms. There are two shorter (3.31 Å) and two longer (3.63 Å) Ca–Mn bond lengths. There are a spread of Ca–Bi bond distances ranging from 3.25–3.34 Å. There are two inequivalent Mn sites. In the first Mn site, Mn is bonded in a 10-coordinate geometry to six Ca and four Bi atoms. There are a spread of Mn–Bi bond distances ranging from 2.82–2.96 Å. In the second Mn site, Mn is bonded in a 4-coordinate geometry to three Ca and four Bi atoms. There are a spread of Mn–Bi bond distances ranging from 2.82–2.95 Å. There are five inequivalent Bi sites. In the first Bi site, Bi is bonded in a 8-coordinate geometry to six Ca and two Mn atoms. In the second Bi site, Bi is bonded to six Ca and one Mn atom to form a mixture of distorted edge and corner-sharing BiCa6Mn pentagonal bipyramids. In the third Bi site, Bi is bonded in a 7-coordinate geometry to six Ca and two equivalent Mn atoms. In the fourth Bi site, Bi is bonded in a distorted body-centered cubic geometry to six Ca and two equivalent Mn atoms. In the fifth Bi site, Bi is bonded in a 7-coordinate geometry to five Ca and two equivalent Mn atoms.