Materials Data on Ba2SrMg4F14 by Materials Project
Ba2SrMg4F14 crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Ba2+ is bonded in a 1-coordinate geometry to eleven F1- atoms. There are a spread of Ba–F bond distances ranging from 2.49–3.10 Å. Sr2+ is bonded in a distorted body-centered cubic geometry to eight F1- atoms. There are a spread of Sr–F bond distances ranging from 2.40–2.62 Å. There are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six F1- atoms to form corner-sharing MgF6 octahedra. The corner-sharing octahedra tilt angles range from 39–46°. There are a spread of Mg–F bond distances ranging from 1.97–2.05 Å. In the second Mg2+ site, Mg2+ is bonded to six F1- atoms to form corner-sharing MgF6 octahedra. The corner-sharing octahedra tilt angles range from 42–53°. There are a spread of Mg–F bond distances ranging from 1.92–2.04 Å. There are seven inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two equivalent Ba2+ and two equivalent Mg2+ atoms. In the second F1- site, F1- is bonded in a 4-coordinate geometry to two equivalent Sr2+ and two equivalent Mg2+ atoms. In the third F1- site, F1- is bonded in a 4-coordinate geometry to one Ba2+, one Sr2+, and two Mg2+ atoms. In the fourth F1- site, F1- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and one Mg2+ atom. In the fifth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two equivalent Ba2+ and two equivalent Mg2+ atoms. In the sixth F1- site, F1- is bonded to two equivalent Ba2+ and two equivalent Sr2+ atoms to form distorted edge-sharing FBa2Sr2 tetrahedra. In the seventh F1- site, F1- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two Mg2+ atoms.