Materials Data on K2Na2IrO4 by Materials Project
K2Na2IrO4 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 in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.69–2.79 Å. In the second 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 2.75–2.97 Å. There are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.31–2.46 Å. In the second Na1+ site, Na1+ is bonded to five O2- atoms to form edge-sharing NaO5 trigonal bipyramids. There are a spread of Na–O bond distances ranging from 2.33–2.45 Å. Ir4+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Ir–O bond distances ranging from 1.93–1.95 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to three K1+, two Na1+, and one Ir4+ atom. In the second O2- site, O2- is bonded in a 6-coordinate geometry to three K1+, two Na1+, and one Ir4+ atom. In the third O2- site, O2- is bonded in a 6-coordinate geometry to one K1+, four Na1+, and one Ir4+ atom. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to three K1+, two Na1+, and one Ir4+ atom.