Materials Data on K6NaAu2IO8 by Materials Project
K6NaAu2O8I crystallizes in the monoclinic P2/c space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.68–3.19 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.78–3.01 Å. In the third K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.72–3.02 Å. In the fourth K1+ site, K1+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are two shorter (2.66 Å) and two longer (2.73 Å) K–O bond lengths. Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.39–2.54 Å. There are two inequivalent Au5+ sites. In the first Au5+ site, Au5+ is bonded in a linear geometry to two equivalent O2- atoms. Both Au–O bond lengths are 2.04 Å. In the second Au5+ site, Au5+ is bonded in a linear geometry to two equivalent O2- atoms. Both Au–O bond lengths are 2.03 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to four K1+, one Na1+, and one I1- atom to form a mixture of distorted edge, corner, and face-sharing OK4NaI octahedra. The corner-sharing octahedra tilt angles range from 0–58°. The O–I bond length is 1.93 Å. In the second O2- site, O2- is bonded in a 6-coordinate geometry to four K1+ and two Au5+ atoms. In the third O2- site, O2- is bonded to four K1+, one Na1+, and one I1- atom to form a mixture of distorted edge, corner, and face-sharing OK4NaI octahedra. The corner-sharing octahedra tilt angles range from 0–49°. The O–I bond length is 1.92 Å. In the fourth O2- site, O2- is bonded to four K1+, one Na1+, and one I1- atom to form a mixture of distorted edge, corner, and face-sharing OK4NaI octahedra. The corner-sharing octahedra tilt angles range from 0–58°. The O–I bond length is 1.94 Å. I1- is bonded in an octahedral geometry to six O2- atoms.