DOE OSTI2020
Mg(ReO4)2 crystallizes in the trigonal P31m space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six ReO4 tetrahedra. There are three shorter (2.09 Å) and three longer (2.16 Å) Mg–O bond lengths. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six ReO4 tetrahedra. There are three shorter (2.08 Å) and three longer (2.26 Å) Mg–O bond lengths. There are two inequivalent Re7+ sites. In the first Re7+ site, Re7+ is bonded to four O2- atoms to form ReO4 tetrahedra that share corners with three MgO6 octahedra. The corner-sharing octahedra tilt angles range from 11–46°. There are a spread of Re–O bond distances ranging from 1.72–1.77 Å. In the second Re7+ site, Re7+ is bonded to four O2- atoms to form ReO4 tetrahedra that share corners with three MgO6 octahedra. The corner-sharing octahedra tilt angles range from 13–41°. There are a spread of Re–O bond distances ranging from 1.72–1.77 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to one Mg2+ and one Re7+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one Re7+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Mg2+ and one Re7+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Re7+ atom. In the fifth O2- site, O2- is bonded in a linear geometry to one Mg2+ and one Re7+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mg2+ and one Re7+ atom.