Materials Data on Na5Cr2As(CO4)4 by Materials Project
Na5Cr2As(CO4)4 crystallizes in the orthorhombic Fdd2 space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.29–2.60 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.30–2.63 Å. In the third Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are two shorter (2.33 Å) and four longer (2.56 Å) Na–O bond lengths. Cr3+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Cr–O bond distances ranging from 2.01–2.06 Å. There are two inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. All C–O bond lengths are 1.30 Å. In the second C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of C–O bond distances ranging from 1.29–1.31 Å. As5+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.71 Å) and two longer (1.73 Å) As–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Cr3+, and one C4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Cr3+, and one C4+ atom. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+, one Cr3+, and one C4+ atom. In the fourth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+, one Cr3+, and one C4+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Cr3+, and one C4+ atom. In the sixth O2- site, O2- is bonded to three Na1+ and one As5+ atom to form edge-sharing ONa3As trigonal pyramids. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Cr3+, and one C4+ atom. In the eighth O2- site, O2- is bonded in a distorted T-shaped geometry to two Na1+ and one As5+ atom.