Materials Data on Ba(FeAs)2 by Materials Project
BaFe2As2 is alpha bismuth trifluoride-derived structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ba2+ is bonded in a body-centered cubic geometry to eight equivalent As3- atoms. All Ba–As bond lengths are 3.42 Å. Fe2+ is bonded to four equivalent As3- atoms to form a mixture of corner and edge-sharing FeAs4 tetrahedra. All Fe–As bond lengths are 2.32 Å. As3- is bonded in a 8-coordinate geometry to four equivalent Ba2+ and four equivalent Fe2+ atoms.