Materials Data on Ba2Ti2Fe2As4O by Materials Project
Ba2Ti2Fe2As4O crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ba2+ is bonded in a body-centered cubic geometry to eight As3- atoms. There are four shorter (3.45 Å) and four longer (3.47 Å) Ba–As bond lengths. Ti3+ is bonded in a distorted linear geometry to four equivalent As3- and two equivalent O2- atoms. All Ti–As bond lengths are 2.71 Å. Both Ti–O bond lengths are 2.04 Å. Fe2+ is bonded to four equivalent As3- atoms to form a mixture of edge and corner-sharing FeAs4 tetrahedra. All Fe–As bond lengths are 2.61 Å. There are two inequivalent As3- sites. In the first As3- site, As3- is bonded in a 8-coordinate geometry to four equivalent Ba2+ and four equivalent Fe2+ atoms. In the second As3- site, As3- is bonded in a 8-coordinate geometry to four equivalent Ba2+ and four equivalent Ti3+ atoms. O2- is bonded in a square co-planar geometry to four equivalent Ti3+ atoms.