DOE OSTI2020
K2CoCl4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to seven Cl1- atoms to form KCl7 pentagonal bipyramids that share corners with two equivalent KCl7 pentagonal bipyramids, corners with five equivalent CoCl4 tetrahedra, edges with two equivalent KCl7 pentagonal bipyramids, and an edgeedge with one CoCl4 tetrahedra. There are a spread of K–Cl bond distances ranging from 3.13–3.52 Å. In the second K1+ site, K1+ is bonded in a 7-coordinate geometry to seven Cl1- atoms. There are a spread of K–Cl bond distances ranging from 3.19–3.45 Å. Co2+ is bonded to four Cl1- atoms to form CoCl4 tetrahedra that share corners with five equivalent KCl7 pentagonal bipyramids and an edgeedge with one KCl7 pentagonal bipyramid. There are a spread of Co–Cl bond distances ranging from 2.25–2.28 Å. There are four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 4-coordinate geometry to three K1+ and one Co2+ atom. In the second Cl1- site, Cl1- is bonded in a 5-coordinate geometry to four K1+ and one Co2+ atom. In the third Cl1- site, Cl1- is bonded in a 1-coordinate geometry to four K1+ and one Co2+ atom. In the fourth Cl1- site, Cl1- is bonded in a 4-coordinate geometry to three K1+ and one Co2+ atom.