Materials Data on Ba4As2O by Materials Project
Ba4As2O is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to five equivalent As3- and one O2- atom. There are one shorter (3.29 Å) and four longer (3.76 Å) Ba–As bond lengths. The Ba–O bond length is 3.07 Å. In the second Ba2+ site, Ba2+ is bonded in a distorted linear geometry to four equivalent As3- and two equivalent O2- atoms. All Ba–As bond lengths are 3.53 Å. Both Ba–O bond lengths are 2.61 Å. As3- is bonded in a 9-coordinate geometry to nine Ba2+ atoms. O2- is bonded to six Ba2+ atoms to form corner-sharing OBa6 octahedra. The corner-sharing octahedral tilt angles are 0°.