Materials Data on BaEu2O4 by Materials Project

Eu2BaO4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ba–O bond distances ranging from 2.77–3.02 Å. There are two inequivalent Eu3+ sites. In the first Eu3+ site, Eu3+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing EuO6 octahedra. The corner-sharing octahedra tilt angles range from 50–61°. There are a spread of Eu–O bond distances ranging from 2.33–2.44 Å. In the second Eu3+ site, Eu3+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing EuO6 octahedra. The corner-sharing octahedra tilt angles range from 50–61°. There are two shorter (2.34 Å) and four longer (2.42 Å) Eu–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Ba2+ and three Eu3+ atoms. In the second O2- site, O2- is bonded to two equivalent Ba2+ and three equivalent Eu3+ atoms to form a mixture of distorted corner and edge-sharing OBa2Eu3 square pyramids. In the third O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Ba2+ and three Eu3+ atoms. In the fourth O2- site, O2- is bonded to two equivalent Ba2+ and three equivalent Eu3+ atoms to form a mixture of distorted corner and edge-sharing OBa2Eu3 trigonal bipyramids.