Materials Data on Li2LaNb6O18 by Materials Project
(Li)2LaNb6O18 crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional and consists of two litio molecules and one LaNb6O18 framework. In the LaNb6O18 framework, La is bonded to twelve O atoms to form LaO12 cuboctahedra that share faces with two equivalent LaO12 cuboctahedra and faces with eight equivalent NbO6 octahedra. There are a spread of La–O bond distances ranging from 2.64–2.75 Å. There are two inequivalent Nb sites. In the first Nb site, Nb is bonded to six O 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 5–16°. There are a spread of Nb–O bond distances ranging from 1.94–2.07 Å. In the second Nb site, Nb is bonded to six O atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 0–12°. There are a spread of Nb–O bond distances ranging from 1.96–2.04 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a linear geometry to two equivalent Nb atoms. In the second O site, O is bonded in a distorted rectangular see-saw-like geometry to two equivalent La and two equivalent Nb atoms. In the third O site, O is bonded in a 3-coordinate geometry to one La and two equivalent Nb atoms. In the fourth O site, O is bonded in a linear geometry to two Nb atoms. In the fifth O site, O is bonded in a linear geometry to two equivalent Nb atoms. In the sixth O site, O is bonded in a linear geometry to two equivalent Nb atoms. In the seventh O site, O is bonded to two equivalent La and two equivalent Nb atoms to form a mixture of distorted edge and corner-sharing OLa2Nb2 trigonal pyramids. In the eighth O site, O is bonded in a linear geometry to two equivalent Nb atoms.