Materials Data on Na4Ce(As2O7)2 by Materials Project
Na4Ce(As2O7)2 crystallizes in the tetragonal P4/ncc space group. The structure is three-dimensional. Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.33–2.69 Å. Ce4+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.38 Å) and four longer (2.41 Å) Ce–O bond lengths. As5+ is bonded to four O2- atoms to form corner-sharing AsO4 tetrahedra. There are a spread of As–O bond distances ranging from 1.69–1.83 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Na1+ and one As5+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two equivalent As5+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Ce4+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Ce4+ and one As5+ atom.