Materials Data on K2S2O7 by Materials Project
K2S2O7 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. K1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of K–O bond distances ranging from 2.77–3.27 Å. S6+ is bonded to four O2- atoms to form corner-sharing SO4 tetrahedra. There are a spread of S–O bond distances ranging from 1.45–1.67 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent K1+ and one S6+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent K1+ and one S6+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent K1+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent S6+ atoms.