Materials Data on K3(FeO2)4 by Materials Project
K3(FeO2)4 crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 4-coordinate geometry to four equivalent O atoms. All K–O bond lengths are 3.25 Å. In the second K site, K is bonded in a 8-coordinate geometry to two equivalent O atoms. Both K–O bond lengths are 3.19 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to four equivalent O atoms to form distorted corner-sharing FeO4 tetrahedra. All Fe–O bond lengths are 1.83 Å. In the second Fe site, Fe is bonded to four equivalent O atoms to form corner-sharing FeO4 tetrahedra. All Fe–O bond lengths are 1.87 Å. In the third Fe site, Fe is bonded to four O atoms to form corner-sharing FeO4 tetrahedra. All Fe–O bond lengths are 1.86 Å. There are two inequivalent O sites. In the first O site, O is bonded in a linear geometry to two Fe atoms. In the second O site, O is bonded in a distorted linear geometry to two K and two Fe atoms.