Materials Data on TiNbTl(O2F)2 by Materials Project
TiNbTl(O2F)2 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. Ti4+ is bonded to three O2- and three F1- atoms to form TiO3F3 octahedra that share corners with two equivalent TiO3F3 octahedra and corners with four equivalent NbO5F octahedra. The corner-sharing octahedra tilt angles range from 33–42°. There are a spread of Ti–O bond distances ranging from 1.86–1.90 Å. There are a spread of Ti–F bond distances ranging from 2.00–2.07 Å. Nb5+ is bonded to five O2- and one F1- atom to form NbO5F octahedra that share corners with two equivalent NbO5F octahedra and corners with four equivalent TiO3F3 octahedra. The corner-sharing octahedra tilt angles range from 33–42°. There are a spread of Nb–O bond distances ranging from 1.94–2.03 Å. The Nb–F bond length is 2.17 Å. Tl1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are two shorter (2.88 Å) and one longer (3.10 Å) Tl–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Ti4+ and one Nb5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Nb5+ and one Tl1+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ti4+, one Nb5+, and one Tl1+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Ti4+, one Nb5+, and one Tl1+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Ti4+ and one Nb5+ atom. In the second F1- site, F1- is bonded in a bent 150 degrees geometry to two equivalent Ti4+ atoms.