Materials Data on GdNb5Ag2O15 by Materials Project
GdNb5Ag2O15 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Gd3+ is bonded to twelve O2- atoms to form GdO12 cuboctahedra that share faces with two equivalent GdO12 cuboctahedra and faces with eight equivalent NbO6 octahedra. There are four shorter (2.60 Å) and eight longer (2.67 Å) Gd–O bond lengths. There are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 0–31°. There is two shorter (1.97 Å) and four longer (2.02 Å) Nb–O bond length. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with two equivalent GdO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 13–44°. There are a spread of Nb–O bond distances ranging from 1.92–2.09 Å. Ag1+ is bonded in a 2-coordinate geometry to nine O2- atoms. There are a spread of Ag–O bond distances ranging from 2.66–3.14 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Nb5+ and two equivalent Ag1+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Gd3+, two equivalent Nb5+, and one Ag1+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Nb5+ and two equivalent Ag1+ atoms. In the fourth O2- site, O2- is bonded in a linear geometry to two equivalent Nb5+ and two equivalent Ag1+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Gd3+ and two equivalent Nb5+ atoms.