Materials Data on Na2CoCl4 by Materials Project
Na2CoCl4 is Spinel-like structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six Cl1- atoms to form NaCl6 octahedra that share corners with four equivalent NaCl6 octahedra, corners with two equivalent CoCl4 tetrahedra, edges with four NaCl6 octahedra, and edges with two equivalent CoCl4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–62°. There are a spread of Na–Cl bond distances ranging from 2.81–2.89 Å. In the second Na1+ site, Na1+ is bonded to six Cl1- atoms to form NaCl6 octahedra that share corners with eight NaCl6 octahedra, corners with four equivalent CoCl4 tetrahedra, edges with two equivalent NaCl6 octahedra, and an edgeedge with one CoCl4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–62°. There are a spread of Na–Cl bond distances ranging from 2.83–2.92 Å. Co2+ is bonded to four Cl1- atoms to form CoCl4 tetrahedra that share corners with six NaCl6 octahedra and edges with three NaCl6 octahedra. The corner-sharing octahedra tilt angles range from 55–59°. There are a spread of Co–Cl bond distances ranging from 2.25–2.28 Å. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a rectangular see-saw-like geometry to three Na1+ and one Co2+ atom. In the second Cl1- site, Cl1- is bonded to three Na1+ and one Co2+ atom to form distorted corner-sharing ClNa3Co trigonal pyramids. In the third Cl1- site, Cl1- is bonded in a rectangular see-saw-like geometry to three Na1+ and one Co2+ atom.