Materials Data on SrMnBi2 by Materials Project
SrMnBi2 is Parent of FeAs superconductors-derived structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded to four Mn and eight Bi atoms to form distorted SrMn4Bi8 cuboctahedra that share corners with eight equivalent SrMn4Bi8 cuboctahedra, corners with eight MnSr4Bi4 tetrahedra, edges with four equivalent SrMn4Bi8 cuboctahedra, edges with four MnSr4Bi4 tetrahedra, and faces with five equivalent SrMn4Bi8 cuboctahedra. All Sr–Mn bond lengths are 3.74 Å. There are four shorter (3.52 Å) and four longer (3.57 Å) Sr–Bi bond lengths. In the second Sr site, Sr is bonded to four Mn and eight Bi atoms to form distorted SrMn4Bi8 cuboctahedra that share corners with eight equivalent SrMn4Bi8 cuboctahedra, corners with eight MnSr4Bi4 tetrahedra, edges with four equivalent SrMn4Bi8 cuboctahedra, edges with four MnSr4Bi4 tetrahedra, and faces with five equivalent SrMn4Bi8 cuboctahedra. All Sr–Mn bond lengths are 3.74 Å. There are four shorter (3.52 Å) and four longer (3.57 Å) Sr–Bi bond lengths. There are two inequivalent Mn sites. In the first Mn site, Mn is bonded to four Sr and four Bi atoms to form distorted MnSr4Bi4 tetrahedra that share corners with eight SrMn4Bi8 cuboctahedra, edges with four SrMn4Bi8 cuboctahedra, edges with four equivalent MnSr4Bi4 tetrahedra, and faces with four equivalent MnSr4Bi4 tetrahedra. All Mn–Bi bond lengths are 2.85 Å. In the second Mn site, Mn is bonded to four Sr and four Bi atoms to form distorted MnSr4Bi4 tetrahedra that share corners with eight SrMn4Bi8 cuboctahedra, edges with four SrMn4Bi8 cuboctahedra, edges with four equivalent MnSr4Bi4 tetrahedra, and faces with four equivalent MnSr4Bi4 tetrahedra. All Mn–Bi bond lengths are 2.85 Å. There are seven inequivalent Bi sites. In the first Bi site, Bi is bonded in a 8-coordinate geometry to four equivalent Sr and four equivalent Bi atoms. All Bi–Bi bond lengths are 3.28 Å. In the second Bi site, Bi is bonded in a distorted body-centered cubic geometry to four equivalent Sr and four equivalent Bi atoms. In the third Bi site, Bi is bonded in a 8-coordinate geometry to four equivalent Sr and four Mn atoms. In the fourth Bi site, Bi is bonded in a 8-coordinate geometry to four equivalent Sr and four Mn atoms. In the fifth Bi site, Bi is bonded in a distorted body-centered cubic geometry to four equivalent Sr and four equivalent Bi atoms. All Bi–Bi bond lengths are 3.28 Å. In the sixth Bi site, Bi is bonded in a distorted body-centered cubic geometry to four equivalent Sr and four equivalent Bi atoms. In the seventh Bi site, Bi is bonded in a 8-coordinate geometry to four equivalent Sr and four Mn atoms. All Bi–Sr bond lengths are 3.52 Å. All Bi–Mn bond lengths are 2.85 Å.