Materials Data on MnFeH4NF6 by Materials Project
NH4MnFeF6 crystallizes in the orthorhombic Pnc2 space group. The structure is three-dimensional and consists of two ammonia molecules, six ammonium molecules, and one Mn2Fe2HF12 framework. In the Mn2Fe2HF12 framework, there are two inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded in a 5-coordinate geometry to five F1- atoms. There are a spread of Mn–F bond distances ranging from 2.03–2.28 Å. In the second Mn2+ site, Mn2+ is bonded to six F1- atoms to form MnF6 octahedra that share corners with four FeF6 octahedra and an edgeedge with one FeF6 octahedra. The corner-sharing octahedra tilt angles range from 21–45°. There are a spread of Mn–F bond distances ranging from 2.09–2.34 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six F1- atoms to form FeF6 octahedra that share a cornercorner with one MnF6 octahedra and an edgeedge with one MnF6 octahedra. The corner-sharing octahedral tilt angles are 33°. There are a spread of Fe–F bond distances ranging from 1.93–2.04 Å. In the second Fe3+ site, Fe3+ is bonded to six F1- atoms to form distorted FeF6 octahedra that share corners with three equivalent MnF6 octahedra. The corner-sharing octahedra tilt angles range from 21–45°. There are a spread of Fe–F bond distances ranging from 1.97–2.37 Å. H1+ is bonded in a bent 150 degrees geometry to two F1- atoms. There is one shorter (1.04 Å) and one longer (1.35 Å) H–F bond length. There are twelve inequivalent F1- sites. In the first F1- site, F1- is bonded in a bent 120 degrees geometry to one Mn2+ and one Fe3+ atom. In the second F1- site, F1- is bonded in a 1-coordinate geometry to one Mn2+, one Fe3+, and one H1+ atom. In the third F1- site, F1- is bonded in a bent 150 degrees geometry to one Mn2+ and one Fe3+ atom. In the fourth F1- site, F1- is bonded in a bent 150 degrees geometry to one Mn2+ and one Fe3+ atom. In the fifth F1- site, F1- is bonded in a bent 150 degrees geometry to one Mn2+ and one Fe3+ atom. In the sixth F1- site, F1- is bonded in a bent 150 degrees geometry to one Mn2+ and one Fe3+ atom. In the seventh F1- site, F1- is bonded in a bent 150 degrees geometry to one Mn2+ and one Fe3+ atom. In the eighth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Mn2+ and one Fe3+ atom. In the ninth F1- site, F1- is bonded in a single-bond geometry to one Fe3+ and one H1+ atom. In the tenth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Mn2+ and one Fe3+ atom. In the eleventh F1- site, F1- is bonded in a distorted water-like geometry to one Mn2+ and one Fe3+ atom. In the twelfth F1- site, F1- is bonded in a water-like geometry to one Mn2+ and one Fe3+ atom.