Materials Data on Co6O7F5 by Materials Project
Co6O7F5 is zeta iron carbide-derived structured and crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent Co+3.17+ sites. In the first Co+3.17+ site, Co+3.17+ is bonded to three O2- and three F1- atoms to form CoO3F3 octahedra that share corners with eight CoO5F octahedra and edges with two CoO3F3 octahedra. The corner-sharing octahedra tilt angles range from 44–51°. There is one shorter (1.82 Å) and two longer (1.87 Å) Co–O bond length. There is two shorter (1.89 Å) and one longer (1.96 Å) Co–F bond length. In the second Co+3.17+ site, Co+3.17+ is bonded to two equivalent O2- and four F1- atoms to form CoO2F4 octahedra that share corners with eight equivalent CoO4F2 octahedra and edges with two equivalent CoO3F3 octahedra. The corner-sharing octahedra tilt angles range from 52–53°. Both Co–O bond lengths are 1.90 Å. There are two shorter (2.03 Å) and two longer (2.06 Å) Co–F bond lengths. In the third Co+3.17+ site, Co+3.17+ is bonded to five O2- and one F1- atom to form distorted CoO5F octahedra that share corners with eight equivalent CoO3F3 octahedra and edges with two equivalent CoO4F2 octahedra. The corner-sharing octahedra tilt angles range from 47–51°. There is four shorter (1.86 Å) and one longer (1.97 Å) Co–O bond length. The Co–F bond length is 2.51 Å. In the fourth Co+3.17+ site, Co+3.17+ is bonded to four O2- and two F1- atoms to form CoO4F2 octahedra that share corners with eight CoO3F3 octahedra and edges with two CoO5F octahedra. The corner-sharing octahedra tilt angles range from 44–53°. There is two shorter (1.87 Å) and two longer (1.90 Å) Co–O bond length. There are one shorter (2.15 Å) and one longer (2.22 Å) Co–F bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to three Co+3.17+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to three Co+3.17+ atoms. In the third O2- site, O2- is bonded in a trigonal planar geometry to three Co+3.17+ atoms. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to three Co+3.17+ atoms. In the second F1- site, F1- is bonded in a distorted L-shaped geometry to three Co+3.17+ atoms. In the third F1- site, F1- is bonded in a 3-coordinate geometry to three Co+3.17+ atoms.