Materials Data on Eu4As2O by Materials Project
Eu4As2O is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Eu2+ sites. In the first Eu2+ site, Eu2+ is bonded in a distorted linear geometry to four equivalent As3- and two equivalent O2- atoms. All Eu–As bond lengths are 3.22 Å. Both Eu–O bond lengths are 2.38 Å. In the second Eu2+ site, Eu2+ is bonded in a 6-coordinate geometry to five equivalent As3- and one O2- atom. There are one shorter (3.05 Å) and four longer (3.42 Å) Eu–As bond lengths. The Eu–O bond length is 2.78 Å. As3- is bonded in a 9-coordinate geometry to nine Eu2+ atoms. O2- is bonded to six Eu2+ atoms to form corner-sharing OEu6 octahedra. The corner-sharing octahedral tilt angles are 0°.