Materials Data on K2Se2O7 by Materials Project
K2Se2O7 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.80–3.25 Å. Se6+ is bonded to four O2- atoms to form corner-sharing SeO4 tetrahedra. There are a spread of Se–O bond distances ranging from 1.64–1.84 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three equivalent K1+ and one Se6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three equivalent K1+ and one Se6+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+ and one Se6+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent Se6+ atoms.