DOE OSTI2020
ReSi2(PO5)3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Re7+ is bonded to six O2- atoms to form distorted ReO6 octahedra that share a cornercorner with one ReO6 octahedra and corners with three PO4 tetrahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Re–O bond distances ranging from 1.72–2.11 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to six O2- atoms to form SiO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.75–1.82 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with three PO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.60–1.64 Å. There are three inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one ReO6 octahedra, corners with two equivalent SiO6 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 29–48°. There are a spread of P–O bond distances ranging from 1.52–1.59 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one ReO6 octahedra, corners with two equivalent SiO6 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 29–46°. There are a spread of P–O bond distances ranging from 1.51–1.58 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one ReO6 octahedra, corners with two equivalent SiO6 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 27–47°. There are a spread of P–O bond distances ranging from 1.52–1.59 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two equivalent Re7+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two equivalent Si4+ atoms. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Re7+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Si4+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Re7+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Si4+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Si4+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one Si4+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to one Si4+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a single-bond geometry to one Re7+ atom. In the eleventh O2- site, O2- is bonded in a bent 150 degrees geometry to one Re7+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Si4+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Si4+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Si4+ and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a single-bond geometry to one Re7+ atom. In the sixteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Si4+ and one P5+ atom.