Materials Data on MgTl2(PO4)4 by Materials Project
MgTl2(PO4)4 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of one MgTl2(PO4)4 sheet oriented in the (1, 0, 1) direction. Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four PO4 tetrahedra. There are four shorter (2.05 Å) and two longer (2.17 Å) Mg–O bond lengths. Tl is bonded in a 3-coordinate geometry to three O atoms. There are a spread of Tl–O bond distances ranging from 2.58–2.70 Å. There are two inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one MgO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 44°. There are a spread of P–O bond distances ranging from 1.52–1.62 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one MgO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of P–O bond distances ranging from 1.52–1.61 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to one Tl and one P atom. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one Tl and one P atom. In the third O site, O is bonded in a distorted bent 150 degrees geometry to one Mg and one P atom. In the fourth O site, O is bonded in a distorted bent 150 degrees geometry to two P atoms. In the fifth O site, O is bonded in a single-bond geometry to one P atom. In the sixth O site, O is bonded in a distorted bent 150 degrees geometry to one Tl and one P atom. In the seventh O site, O is bonded in a distorted bent 150 degrees geometry to one Mg and one P atom. In the eighth O site, O is bonded in a single-bond geometry to one Mg atom.