Materials Data on Sm2Fe2Se2O3 by Materials Project
Sm2Fe2Se2O3 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Sm3+ is bonded in a 4-coordinate geometry to four equivalent Se2- and four equivalent O2- atoms. All Sm–Se bond lengths are 3.32 Å. All Sm–O bond lengths are 2.32 Å. Fe2+ is bonded in a distorted linear geometry to four equivalent Se2- and two equivalent O2- atoms. All Fe–Se bond lengths are 2.77 Å. Both Fe–O bond lengths are 2.03 Å. Se2- is bonded in a 12-coordinate geometry to four equivalent Sm3+ and four equivalent Fe2+ atoms. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Sm3+ atoms to form a mixture of distorted edge and corner-sharing OSm4 tetrahedra. In the second O2- site, O2- is bonded in a square co-planar geometry to four equivalent Fe2+ atoms.