Materials Data on Na2ZrGe2O7 by Materials Project
Na2ZrGe2O7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.46–2.91 Å. In the second Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.36–2.58 Å. Zr4+ is bonded to six O2- atoms to form ZrO6 octahedra that share corners with six GeO4 tetrahedra. There are a spread of Zr–O bond distances ranging from 2.07–2.18 Å. There are two inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with three equivalent ZrO6 octahedra and a cornercorner with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 29–58°. There are a spread of Ge–O bond distances ranging from 1.74–1.83 Å. In the second Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with three equivalent ZrO6 octahedra and a cornercorner with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 14–54°. There are a spread of Ge–O bond distances ranging from 1.74–1.83 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Zr4+, and one Ge4+ atom. In the second O2- site, O2- is bonded to two equivalent Na1+ and two Ge4+ atoms to form distorted ONa2Ge2 trigonal pyramids that share a cornercorner with one ONa2ZrGe trigonal pyramid and edges with two ONa2Ge2 trigonal pyramids. In the third O2- site, O2- is bonded in a 3-coordinate geometry to three Na1+, one Zr4+, and one Ge4+ atom. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Na1+, one Zr4+, and one Ge4+ atom. In the fifth O2- site, O2- is bonded to two Na1+, one Zr4+, and one Ge4+ atom to form a mixture of distorted corner and edge-sharing ONa2ZrGe trigonal pyramids. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Zr4+, and one Ge4+ atom. In the seventh O2- site, O2- is bonded in a distorted T-shaped geometry to one Na1+, one Zr4+, and one Ge4+ atom.