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DOE OSTI · 1744787

Materials Data on EuMnBi2 by Materials Project

Abstract

EuMnBi2 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 Eu sites. In the first Eu site, Eu is bonded to four Mn and eight Bi atoms to form distorted EuMn4Bi8 cuboctahedra that share corners with eight equivalent EuMn4Bi8 cuboctahedra, corners with eight MnEu4Bi4 tetrahedra, edges with four equivalent EuMn4Bi8 cuboctahedra, edges with four MnEu4Bi4 tetrahedra, and faces with five equivalent EuMn4Bi8 cuboctahedra. All Eu–Mn bond lengths are 3.66 Å. There are four shorter (3.45 Å) and four longer (3.47 Å) Eu–Bi bond lengths. In the second Eu site, Eu is bonded to four Mn and eight Bi atoms to form distorted EuMn4Bi8 cuboctahedra that share corners with eight equivalent EuMn4Bi8 cuboctahedra, corners with eight MnEu4Bi4 tetrahedra, edges with four equivalent EuMn4Bi8 cuboctahedra, edges with four MnEu4Bi4 tetrahedra, and faces with five equivalent EuMn4Bi8 cuboctahedra. All Eu–Mn bond lengths are 3.66 Å. There are four shorter (3.45 Å) and four longer (3.47 Å) Eu–Bi bond lengths. There are two inequivalent Mn sites. In the first Mn site, Mn is bonded to four Eu and four Bi atoms to form distorted MnEu4Bi4 tetrahedra that share corners with eight EuMn4Bi8 cuboctahedra, edges with four EuMn4Bi8 cuboctahedra, edges with four equivalent MnEu4Bi4 tetrahedra, and faces with four equivalent MnEu4Bi4 tetrahedra. All Mn–Bi bond lengths are 2.87 Å. In the second Mn site, Mn is bonded to four Eu and four Bi atoms to form distorted MnEu4Bi4 tetrahedra that share corners with eight EuMn4Bi8 cuboctahedra, edges with four EuMn4Bi8 cuboctahedra, edges with four equivalent MnEu4Bi4 tetrahedra, and faces with four equivalent MnEu4Bi4 tetrahedra. All Mn–Bi bond lengths are 2.87 Å. There are five inequivalent Bi sites. In the first Bi site, Bi is bonded in a 4-coordinate geometry to four equivalent Eu and four equivalent Bi atoms. All Bi–Bi bond lengths are 3.28 Å. In the second Bi site, Bi is bonded in a 8-coordinate geometry to four equivalent Eu and four equivalent Bi atoms. In the third Bi site, Bi is bonded in a 8-coordinate geometry to four equivalent Eu and four Mn atoms. In the fourth Bi site, Bi is bonded in a 8-coordinate geometry to four equivalent Eu and four Mn atoms. In the fifth Bi site, Bi is bonded in a 8-coordinate geometry to four equivalent Eu and four equivalent Bi atoms. All Bi–Bi bond lengths are 3.28 Å.

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2020-04-26. Materials Data on EuMnBi2 by Materials Project. https://doi.org/10.17188/1744787

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