DOE OSTI2020
Bi2TeO5 crystallizes in the orthorhombic Aem2 space group. The structure is two-dimensional and consists of one Bi2TeO5 sheet oriented in the (0, 0, 1) direction. there are three inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Bi–O bond distances ranging from 2.21–2.79 Å. In the second Bi3+ site, Bi3+ is bonded in a distorted square pyramidal geometry to five O2- atoms. There are a spread of Bi–O bond distances ranging from 2.09–2.46 Å. In the third Bi3+ site, Bi3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Bi–O bond distances ranging from 2.23–3.07 Å. Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.89–1.92 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to four Bi3+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Bi3+ and one Te4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Bi3+ and one Te4+ atom. In the fourth O2- site, O2- is bonded to four equivalent Bi3+ atoms to form a mixture of distorted edge and corner-sharing OBi4 tetrahedra. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three Bi3+ and one Te4+ atom. In the sixth O2- site, O2- is bonded to four Bi3+ atoms to form a mixture of distorted edge and corner-sharing OBi4 tetrahedra.