Materials Data on BaO2 by Materials Project

BaO2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Ba sites. In the first Ba site, Ba is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ba–O bond distances ranging from 2.61–2.92 Å. In the second Ba site, Ba is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Ba–O bond distances ranging from 2.62–2.92 Å. There are four inequivalent O sites. In the first O site, O is bonded to four Ba atoms to form a mixture of corner and edge-sharing OBa4 tetrahedra. In the second O site, O is bonded in a rectangular see-saw-like geometry to four Ba atoms. In the third O site, O is bonded in a distorted T-shaped geometry to three Ba atoms. In the fourth O site, O is bonded in a rectangular see-saw-like geometry to four Ba atoms.