DOI: 10.17188/1713492
title: Materials Data on NaCa4Nb5O17 by Materials Project

description: NaCa4Nb5O17 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Na1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Na–O bond distances ranging from 2.36–2.92 Å. There are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.55 Å. In the second Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.40–2.66 Å. In the third Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.39–2.59 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.38–2.67 Å. There are six inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 27–36°. There are a spread of Nb–O bond distances ranging from 1.84–2.27 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 29–30°. There are two shorter (2.01 Å) and four longer (2.02 Å) Nb–O bond lengths. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 26–34°. There are a spread of Nb–O bond distances ranging from 1.88–2.25 Å. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 28–30°. There are a spread of Nb–O bond distances ranging from 2.00–2.03 Å. In the fifth Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 26–36°. There are a spread of Nb–O bond distances ranging from 1.90–2.19 Å. In the sixth Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 26–35°. There are a spread of Nb–O bond distances ranging from 1.89–2.19 Å. There are seventeen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to one Na1+, two equivalent Ca2+, and two Nb5+ atoms. In the second O2- site, O2- is bonded to one Na1+, one Ca2+, and two Nb5+ atoms to form distorted corner-sharing ONaCaNb2 tetrahedra. In the third O2- site, O2- is bonded in a 5-coordinate geometry to one Na1+, two Ca2+, and two Nb5+ atoms. In the fourth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+ and two Nb5+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, and two Nb5+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two Ca2+ and one Nb5+ atom. In the seventh O2- site, O2- is bonded to three Ca2+ and one Nb5+ atom to form a mixture of distorted edge and corner-sharing OCa3Nb tetrahedra. In the eighth O2- site, O2- is bonded to one Na1+, one Ca2+, and two Nb5+ atoms to form distorted ONaCaNb2 tetrahedra that share corners with two OCa3Nb tetrahedra and an edgeedge with one OCa2Nb2 tetrahedra. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Nb5+ atoms. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+ and two Nb5+ atoms. In the eleventh O2- site, O2- is bonded in a 5-coordinate geometry to one Na1+, two Ca2+, and two Nb5+ atoms. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+ and two Nb5+ atoms. In the thirteenth O2- site, O2- is bonded in a 5-coordinate geometry to one Na1+, two equivalent Ca2+, and two Nb5+ atoms. In the fourteenth O2- site, O2- is bonded to three Ca2+ and one Nb5+ atom to form a mixture of distorted edge and corner-sharing OCa3Nb tetrahedra. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Ca2+, and two Nb5+ atoms. In the sixteenth O2- site, O2- is bonded to two Ca2+ and two Nb5+ atoms to form a mixture of distorted edge and corner-sharing OCa2Nb2 tetrahedra. In the seventeenth O2- site, O2- is bonded to three Ca2+ and one Nb5+ atom to form a mixture of distorted edge and corner-sharing OCa3Nb tetrahedra.