Materials Data on KAsSe3O by Materials Project
KAsSe3O crystallizes in the monoclinic Cc space group. The structure is two-dimensional and consists of two KAsSe3O sheets oriented in the (1, 0, 0) direction. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a T-shaped geometry to three O2- atoms. There are a spread of K–O bond distances ranging from 2.82–3.15 Å. In the second K1+ site, K1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of K–O bond distances ranging from 2.79–3.21 Å. There are two inequivalent As1- sites. In the first As1- site, As1- is bonded in a rectangular see-saw-like geometry to four Se+0.67+ atoms. There are a spread of As–Se bond distances ranging from 2.43–2.66 Å. In the second As1- site, As1- is bonded to four Se+0.67+ atoms to form corner-sharing AsSe4 trigonal pyramids. There are a spread of As–Se bond distances ranging from 2.45–2.79 Å. There are six inequivalent Se+0.67+ sites. In the first Se+0.67+ site, Se+0.67+ is bonded in a distorted linear geometry to two equivalent As1- atoms. In the second Se+0.67+ site, Se+0.67+ is bonded in a bent 150 degrees geometry to two equivalent As1- atoms. In the third Se+0.67+ site, Se+0.67+ is bonded in a single-bond geometry to one As1- atom. In the fourth Se+0.67+ site, Se+0.67+ is bonded in a single-bond geometry to one As1- atom. In the fifth Se+0.67+ site, Se+0.67+ is bonded in a distorted water-like geometry to one As1- and one O2- atom. The Se–O bond length is 1.78 Å. In the sixth Se+0.67+ site, Se+0.67+ is bonded in a distorted water-like geometry to one As1- and one O2- atom. The Se–O bond length is 1.77 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three K1+ and one Se+0.67+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three K1+ and one Se+0.67+ atom.