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Materials Data on KLa2NbO6 by Materials Project

KLa2NbO6 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. K1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of K–O bond distances ranging from 2.63–3.01 Å. There are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.44–2.64 Å. In the second La3+ site, La3+ is bonded to seven O2- atoms to form distorted LaO7 hexagonal pyramids that share corners with three equivalent NbO5 trigonal bipyramids, an edgeedge with one LaO7 hexagonal pyramid, and an edgeedge with one NbO5 trigonal bipyramid. There are a spread of La–O bond distances ranging from 2.37–2.61 Å. Nb5+ is bonded to five O2- atoms to form distorted NbO5 trigonal bipyramids that share corners with three equivalent LaO7 hexagonal pyramids and an edgeedge with one LaO7 hexagonal pyramid. There are a spread of Nb–O bond distances ranging from 1.86–2.03 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent K1+, two La3+, and one Nb5+ atom. In the second O2- site, O2- is bonded to four La3+ atoms to form OLa4 tetrahedra that share corners with eight equivalent OLa3Nb tetrahedra and edges with four OLa4 tetrahedra. In the third O2- site, O2- is bonded to three La3+ and one Nb5+ atom to form a mixture of distorted edge and corner-sharing OLa3Nb tetrahedra. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three equivalent K1+, one La3+, and one Nb5+ atom.

36 MATERIALS SCIENCE↗

Materials Data on K2LaNb5O15 by Materials Project

K2LaNb5O15 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to nine O2- atoms. There are a spread of K–O bond distances ranging from 2.86–3.24 Å. La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share faces with two equivalent LaO12 cuboctahedra and faces with eight equivalent NbO6 octahedra. There are four shorter (2.66 Å) and eight longer (2.73 Å) La–O bond lengths. There are two inequivalent Nb5+ sites. In the first 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 LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 10–36°. There are a spread of Nb–O bond distances ranging from 1.92–2.09 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 0–32°. There are two shorter (1.99 Å) and four longer (2.01 Å) Nb–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two equivalent K1+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent La3+ and two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one La3+, and two equivalent Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+ and two equivalent Nb5+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+ and two Nb5+ atoms.

36 MATERIALS SCIENCE↗