Materials Data on Sr6Ge5N2 by Materials Project
Sr6Ge5N2 crystallizes in the orthorhombic Pmmn space group. The structure is three-dimensional. there are four inequivalent Sr sites. In the first Sr site, Sr is bonded in a 2-coordinate geometry to four Ge and two equivalent N atoms. There are a spread of Sr–Ge bond distances ranging from 3.37–3.60 Å. Both Sr–N bond lengths are 2.75 Å. In the second Sr site, Sr is bonded in a distorted single-bond geometry to six Ge and one N atom. There are a spread of Sr–Ge bond distances ranging from 3.27–3.47 Å. The Sr–N bond length is 2.45 Å. In the third Sr site, Sr is bonded in a 5-coordinate geometry to seven Ge atoms. There are a spread of Sr–Ge bond distances ranging from 3.10–3.53 Å. In the fourth Sr site, Sr is bonded in a 4-coordinate geometry to two equivalent Ge and four equivalent N atoms. Both Sr–Ge bond lengths are 3.65 Å. All Sr–N bond lengths are 2.81 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a distorted water-like geometry to one Sr and two equivalent N atoms. Both Ge–N bond lengths are 1.90 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to seven Sr and two equivalent Ge atoms. Both Ge–Ge bond lengths are 2.58 Å. In the third Ge site, Ge is bonded in a 9-coordinate geometry to seven Sr and two equivalent Ge atoms. N is bonded to five Sr and one Ge atom to form a mixture of distorted corner, edge, and face-sharing NSr5Ge octahedra. The corner-sharing octahedral tilt angles are 52°.