Materials Data on NaMgSO4F by Materials Project
NaMg(SO4)F crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Na1+ is bonded in a 7-coordinate geometry to six O2- and one F1- atom. There are a spread of Na–O bond distances ranging from 2.44–2.75 Å. The Na–F bond length is 2.19 Å. Mg2+ is bonded to four O2- and two equivalent F1- atoms to form MgO4F2 octahedra that share corners with two equivalent MgO4F2 octahedra and corners with four equivalent SO4 tetrahedra. The corner-sharing octahedral tilt angles are 41°. There are two shorter (2.14 Å) and two longer (2.16 Å) Mg–O bond lengths. Both Mg–F bond lengths are 1.92 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with four equivalent MgO4F2 octahedra. The corner-sharing octahedra tilt angles range from 35–49°. There is two shorter (1.49 Å) and two longer (1.50 Å) S–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Mg2+, and one S6+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Mg2+, and one S6+ atom. F1- is bonded in a distorted trigonal planar geometry to one Na1+ and two equivalent Mg2+ atoms.