Materials Data on EuMgAl11O19 by Materials Project

Abstract

EuMgAl11O19 is beta indium sulfide-derived structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with twelve AlO6 octahedra. The corner-sharing octahedra tilt angles range from 59–62°. There is three shorter (1.95 Å) and one longer (1.98 Å) Mg–O bond length. Eu3+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of Eu–O bond distances ranging from 2.51–3.06 Å. There are ten inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent AlO6 octahedra, corners with three equivalent MgO4 tetrahedra, a cornercorner with one AlO5 trigonal bipyramid, and edges with five AlO6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of Al–O bond distances ranging from 1.91–1.96 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent AlO6 octahedra, corners with three equivalent MgO4 tetrahedra, a cornercorner with one AlO5 trigonal bipyramid, and edges with five AlO6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of Al–O bond distances ranging from 1.91–1.96 Å. In the third Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent AlO6 octahedra, a cornercorner with one AlO5 trigonal bipyramid, and edges with five AlO6 octahedra. The corner-sharing octahedra tilt angles range from 48–49°. There are a spread of Al–O bond distances ranging from 1.87–1.98 Å. In the fourth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent AlO6 octahedra, a cornercorner with one AlO5 trigonal bipyramid, and edges with five AlO6 octahedra. The corner-sharing octahedral tilt angles are 49°. There are a spread of Al–O bond distances ranging from 1.87–1.98 Å. In the fifth Al3+ site, Al3+ is bonded to six O2- atoms to form distorted AlO6 octahedra that share corners with six AlO6 octahedra, corners with three equivalent AlO5 trigonal bipyramids, and a faceface with one AlO6 octahedra. The corner-sharing octahedral tilt angles are 54°. There is three shorter (1.87 Å) and three longer (2.03 Å) Al–O bond length. In the sixth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six AlO6 octahedra, corners with three equivalent AlO5 trigonal bipyramids, and a faceface with one AlO6 octahedra. The corner-sharing octahedra tilt angles range from 48–49°. There are a spread of Al–O bond distances ranging from 1.89–1.93 Å. In the seventh Al3+ site, Al3+ is bonded to five O2- atoms to form corner-sharing AlO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 37–59°. There are a spread of Al–O bond distances ranging from 1.79–2.28 Å. In the eighth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six equivalent MgO4 tetrahedra and edges with six AlO6 octahedra. All Al–O bond lengths are 1.92 Å. In the ninth Al3+ site, Al3+ is bonded to six O2- atoms to form edge-sharing AlO6 octahedra. There is four shorter (1.95 Å) and two longer (1.96 Å) Al–O bond length. In the tenth Al3+ site, Al3+ is bonded in a 3-coordinate geometry to six O2- atoms. There are a spread of Al–O bond distances ranging from 1.83–2.27 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to one Mg2+ and three Al3+ atoms to form a mixture of distorted edge and corner-sharing OMgAl3 trigonal pyramids. In the second O2- site, O2- is bonded to one Mg2+ and three Al3+ atoms to form a mixture of distorted edge and corner-sharing OMgAl3 tetrahedra. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Al3+ atoms. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Al3+ atoms. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to four Al3+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to four Al3+ atoms. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Eu3+ and three Al3+ atoms. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to one Eu3+ and three Al3+ atoms. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one Eu3+ and four Al3+ atoms. In the tenth O2- site, O2- is bonded in a distorted trigonal pyramidal geometry to one Eu3+ and four Al3+ atoms. In the eleventh O2- site, O2- is bonded to one Mg2+ and three Al3+ atoms to form distorted corner-sharing OMgAl3 trigonal pyramids. In the twelfth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three Al3+ atoms. In the thirteenth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Eu3+ and three Al3+ atoms. In the fourteenth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Eu3+ and three Al3+ atoms.