DOI: 10.17188/1291077
title: Materials Data on Na2CdO2 by Materials Project

description: Na2CdO2 is Ilmenite-like structured and crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are eight inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with two NaO4 tetrahedra, corners with two CdO4 trigonal pyramids, corners with six NaO4 trigonal pyramids, an edgeedge with one NaO4 tetrahedra, an edgeedge with one CdO4 tetrahedra, and edges with two equivalent NaO4 trigonal pyramids. There are a spread of Na–O bond distances ranging from 2.31–2.50 Å. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 trigonal pyramids that share corners with two equivalent NaO4 tetrahedra, corners with two CdO4 tetrahedra, corners with two equivalent CdO4 trigonal pyramids, corners with five NaO4 trigonal pyramids, an edgeedge with one NaO4 tetrahedra, an edgeedge with one CdO4 tetrahedra, and edges with two equivalent NaO4 trigonal pyramids. There are a spread of Na–O bond distances ranging from 2.27–2.48 Å. In the third Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 trigonal pyramids that share corners with two equivalent NaO4 tetrahedra, corners with two CdO4 tetrahedra, corners with two equivalent CdO4 trigonal pyramids, corners with five NaO4 trigonal pyramids, an edgeedge with one CdO4 tetrahedra, an edgeedge with one CdO4 trigonal pyramid, and edges with two NaO4 trigonal pyramids. There are a spread of Na–O bond distances ranging from 2.32–2.44 Å. In the fourth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with two NaO4 tetrahedra, corners with four CdO4 tetrahedra, corners with two CdO4 trigonal pyramids, corners with four NaO4 trigonal pyramids, an edgeedge with one NaO4 tetrahedra, and edges with two NaO4 trigonal pyramids. There are a spread of Na–O bond distances ranging from 2.25–2.52 Å. In the fifth Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 trigonal pyramids that share corners with two NaO4 tetrahedra, corners with four CdO4 tetrahedra, corners with two CdO4 trigonal pyramids, corners with four NaO4 trigonal pyramids, an edgeedge with one CdO4 trigonal pyramid, and edges with three NaO4 trigonal pyramids. There are a spread of Na–O bond distances ranging from 2.35–2.40 Å. In the sixth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 trigonal pyramids that share corners with two NaO4 tetrahedra, corners with two CdO4 trigonal pyramids, corners with six NaO4 trigonal pyramids, an edgeedge with one NaO4 tetrahedra, and edges with three CdO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.25–2.51 Å. In the seventh Na1+ site, Na1+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.27–2.48 Å. In the eighth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 trigonal pyramids that share corners with two equivalent NaO4 tetrahedra, corners with two CdO4 tetrahedra, corners with two equivalent CdO4 trigonal pyramids, corners with five NaO4 trigonal pyramids, edges with two equivalent NaO4 tetrahedra, an edgeedge with one NaO4 trigonal pyramid, and an edgeedge with one CdO4 trigonal pyramid. There are a spread of Na–O bond distances ranging from 2.28–2.42 Å. There are four inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to four O2- atoms to form distorted CdO4 trigonal pyramids that share corners with two NaO4 tetrahedra, corners with four CdO4 tetrahedra, corners with two CdO4 trigonal pyramids, corners with four NaO4 trigonal pyramids, an edgeedge with one NaO4 trigonal pyramid, and an edgeedge with one CdO4 trigonal pyramid. There are a spread of Cd–O bond distances ranging from 2.20–2.46 Å. In the second Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with two equivalent NaO4 tetrahedra, corners with two CdO4 tetrahedra, corners with two equivalent CdO4 trigonal pyramids, corners with five NaO4 trigonal pyramids, an edgeedge with one CdO4 trigonal pyramid, and edges with three NaO4 trigonal pyramids. There are a spread of Cd–O bond distances ranging from 2.23–2.35 Å. In the third Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with two equivalent NaO4 tetrahedra, corners with two CdO4 tetrahedra, corners with two equivalent CdO4 trigonal pyramids, corners with five NaO4 trigonal pyramids, an edgeedge with one NaO4 tetrahedra, and edges with two NaO4 trigonal pyramids. There are a spread of Cd–O bond distances ranging from 2.20–2.40 Å. In the fourth Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 trigonal pyramids that share corners with two NaO4 tetrahedra, corners with two CdO4 trigonal pyramids, corners with six NaO4 trigonal pyramids, an edgeedge with one CdO4 tetrahedra, an edgeedge with one CdO4 trigonal pyramid, and edges with two NaO4 trigonal pyramids. There are a spread of Cd–O bond distances ranging from 2.16–2.37 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded to five Na1+ and one Cd2+ atom to form a mixture of distorted edge and corner-sharing ONa5Cd octahedra. The corner-sharing octahedra tilt angles range from 51–54°. In the second O2- site, O2- is bonded to four Na1+ and two Cd2+ atoms to form ONa4Cd2 octahedra that share corners with five ONa5Cd octahedra, a cornercorner with one ONa3Cd3 pentagonal pyramid, edges with five ONa5Cd octahedra, and an edgeedge with one ONa3Cd3 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 51–57°. In the third O2- site, O2- is bonded to four Na1+ and two equivalent Cd2+ atoms to form distorted ONa4Cd2 octahedra that share corners with four ONa4Cd2 octahedra, corners with two equivalent ONa3Cd3 pentagonal pyramids, and edges with six ONa5Cd octahedra. The corner-sharing octahedra tilt angles range from 57–62°. In the fourth O2- site, O2- is bonded to six Na1+ atoms to form distorted ONa6 octahedra that share corners with four ONa4Cd2 octahedra, corners with two equivalent ONa3Cd3 pentagonal pyramids, and edges with six ONa5Cd octahedra. The corner-sharing octahedra tilt angles range from 54–58°. In the fifth O2- site, O2- is bonded to five Na1+ and one Cd2+ atom to form distorted ONa5Cd octahedra that share corners with six ONa5Cd octahedra, edges with four ONa4Cd2 octahedra, and edges with two equivalent ONa3Cd3 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 51–55°. In the sixth O2- site, O2- is bonded to three Na1+ and three Cd2+ atoms to form distorted ONa3Cd3 octahedra that share corners with four ONa4Cd2 octahedra, corners with two equivalent ONa3Cd3 pentagonal pyramids, and edges with six ONa5Cd octahedra. The corner-sharing octahedra tilt angles range from 54–62°. In the seventh O2- site, O2- is bonded to three Na1+ and three Cd2+ atoms to form a mixture of distorted edge and corner-sharing ONa3Cd3 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 52–58°. In the eighth O2- site, O2- is bonded to four Na1+ and two Cd2+ atoms to form ONa4Cd2 octahedra that share corners with five ONa5Cd octahedra, a cornercorner with one ONa3Cd3 pentagonal pyramid, edges with five ONa5Cd octahedra, and an edgeedge with one ONa3Cd3 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 51–58°. In the ninth O2- site, O2- is bonded to four Na1+ and two equivalent Cd2+ atoms to form distorted ONa4Cd2 octahedra that share corners with six ONa5Cd octahedra, edges with four ONa4Cd2 octahedra, and edges with two equivalent ONa3Cd3 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 51–56°. In the tenth O2- site, O2- is bonded to two equivalent Na1+ and four Cd2+ atoms to form distorted ONa2Cd4 octahedra that share corners with six ONa5Cd octahedra, edges with four ONa4Cd2 octahedra, and edges with two equivalent ONa3Cd3 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 51–58°.