DOE OSTI2020
Eu2Te4O11 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Eu3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Eu–O bond distances ranging from 2.37–2.75 Å. There are two inequivalent Te4+ sites. In the first Te4+ site, Te4+ is bonded in a see-saw-like geometry to four O2- atoms. There are a spread of Te–O bond distances ranging from 1.86–2.35 Å. In the second Te4+ site, Te4+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Te–O bond distances ranging from 1.88–2.61 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Eu3+ and one Te4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Eu3+ and two Te4+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Eu3+ and one Te4+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Te4+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Eu3+ and one Te4+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Eu3+ and two Te4+ atoms.