Materials Data on La4Ti2Se5O4 by Materials Project

Abstract

La4Ti2O4Se5 crystallizes in the orthorhombic Cmc2_1 space group. The structure is two-dimensional and consists of two La4Ti2O4Se5 sheets oriented in the (0, 1, 0) direction. there are eight inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 3-coordinate geometry to four Se2- and three O2- atoms. There are two shorter (3.08 Å) and two longer (3.34 Å) La–Se bond lengths. There are two shorter (2.41 Å) and one longer (2.50 Å) La–O bond lengths. In the second La3+ site, La3+ is bonded in a 3-coordinate geometry to four Se2- and three O2- atoms. There are two shorter (3.10 Å) and two longer (3.34 Å) La–Se bond lengths. There are two shorter (2.40 Å) and one longer (2.48 Å) La–O bond lengths. In the third La3+ site, La3+ is bonded in a distorted bent 120 degrees geometry to four Se2- and two equivalent O2- atoms. There are two shorter (3.13 Å) and two longer (3.23 Å) La–Se bond lengths. Both La–O bond lengths are 2.27 Å. In the fourth La3+ site, La3+ is bonded in a 3-coordinate geometry to three O2- atoms. There are one shorter (2.44 Å) and two longer (2.47 Å) La–O bond lengths. In the fifth La3+ site, La3+ is bonded in a 3-coordinate geometry to three O2- atoms. There are one shorter (2.42 Å) and two longer (2.45 Å) La–O bond lengths. In the sixth La3+ site, La3+ is bonded in a 4-coordinate geometry to four Se2- and four O2- atoms. All La–Se bond lengths are 3.18 Å. There are two shorter (2.36 Å) and two longer (2.50 Å) La–O bond lengths. In the seventh La3+ site, La3+ is bonded in a 3-coordinate geometry to five Se2- and three O2- atoms. There are three shorter (3.15 Å) and two longer (3.33 Å) La–Se bond lengths. There are two shorter (2.44 Å) and one longer (2.49 Å) La–O bond lengths. In the eighth La3+ site, La3+ is bonded in a 3-coordinate geometry to five Se2- and three O2- atoms. There are three shorter (3.15 Å) and two longer (3.34 Å) La–Se bond lengths. There are two shorter (2.44 Å) and one longer (2.48 Å) La–O bond lengths. There are four inequivalent Ti3+ sites. In the first Ti3+ site, Ti3+ is bonded in a 6-coordinate geometry to four Se2- and two O2- atoms. There are two shorter (2.65 Å) and two longer (2.84 Å) Ti–Se bond lengths. There is one shorter (1.94 Å) and one longer (1.99 Å) Ti–O bond length. In the second Ti3+ site, Ti3+ is bonded in a 6-coordinate geometry to four Se2- and two O2- atoms. There are two shorter (2.64 Å) and two longer (2.85 Å) Ti–Se bond lengths. There is one shorter (1.95 Å) and one longer (1.98 Å) Ti–O bond length. In the third Ti3+ site, Ti3+ is bonded in a distorted linear geometry to four Se2- and two O2- atoms. There are two shorter (2.71 Å) and two longer (2.72 Å) Ti–Se bond lengths. There is one shorter (1.95 Å) and one longer (1.96 Å) Ti–O bond length. In the fourth Ti3+ site, Ti3+ is bonded to five Se2- and one O2- atom to form distorted edge-sharing TiSe5O octahedra. There are a spread of Ti–Se bond distances ranging from 2.59–2.67 Å. The Ti–O bond length is 1.89 Å. There are ten inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to four La3+ and two equivalent Ti3+ atoms. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to four La3+ and two equivalent Ti3+ atoms. In the third Se2- site, Se2- is bonded in a 1-coordinate geometry to one Ti3+ atom. In the fourth Se2- site, Se2- is bonded in a 2-coordinate geometry to two equivalent Ti3+ atoms. In the fifth Se2- site, Se2- is bonded in a 2-coordinate geometry to two equivalent Ti3+ atoms. In the sixth Se2- site, Se2- is bonded in a 6-coordinate geometry to four La3+ and two equivalent Ti3+ atoms. In the seventh Se2- site, Se2- is bonded in a 6-coordinate geometry to four La3+ and two equivalent Ti3+ atoms. In the eighth Se2- site, Se2- is bonded in a 6-coordinate geometry to six La3+ atoms. In the ninth Se2- site, Se2- is bonded in a 4-coordinate geometry to two equivalent La3+ and two equivalent Ti3+ atoms. In the tenth Se2- site, Se2- is bonded in a 4-coordinate geometry to two equivalent La3+ and two equivalent Ti3+ atoms. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to three La3+ and one Ti3+ atom to form a mixture of distorted edge and corner-sharing OLa3Ti tetrahedra. In the second O2- site, O2- is bonded to three La3+ and one Ti3+ atom to form a mixture of distorted edge and corner-sharing OLa3Ti tetrahedra. In the third O2- site, O2- is bonded to three La3+ and one Ti3+ atom to form a mixture of distorted edge and corner-sharing OLa3Ti tetrahedra. In the fourth O2- site, O2- is bonded to three La3+ and one Ti3+ atom to form a mixture of distorted edge and corner-sharing OLa3Ti tetrahedra. In the fifth O2- site, O2- is bonded to three La3+ and one Ti3+ atom to form distorted OLa3Ti tetrahedra that share corners with four OLa3Ti tetrahedra and edges with two equivalent OLa4 tetrahedra. In the sixth O2- site, O2- is bonded to three La3+ and one Ti3+ atom to form distorted OLa3Ti tetrahedra that share corners with four OLa3Ti tetrahedra and edges with two equivalent OLa4 tetrahedra. In the seventh O2- site, O2- is bonded to four La3+ atoms to form distorted OLa4 tetrahedra that share corners with two equivalent OLa4 tetrahedra and edges with four OLa3Ti tetrahedra. In the eighth O2- site, O2- is bonded in a trigonal planar geometry to two equivalent La3+ and one Ti3+ atom.