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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on La4Se3O4 by Materials Project

La4Se3O4 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are three inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 4-coordinate geometry to four Se+1.33- and four O2- atoms. There are two shorter (3.23 Å) and two longer (3.37 Å) La–Se bond lengths. There are three shorter (2.41 Å) and one longer (2.43 Å) La–O bond lengths. In the second La3+ site, La3+ is bonded in a 4-coordinate geometry to four equivalent Se+1.33- and four O2- atoms. All La–Se bond lengths are 3.22 Å. There are two shorter (2.40 Å) and two longer (2.43 Å) La–O bond lengths. In the third La3+ site, La3+ is bonded in a 6-coordinate geometry to two equivalent Se+1.33- and four O2- atoms. Both La–Se bond lengths are 3.24 Å. There are two shorter (2.36 Å) and two longer (2.40 Å) La–O bond lengths. There are two inequivalent Se+1.33- sites. In the first Se+1.33- site, Se+1.33- is bonded in a 4-coordinate geometry to four La3+ and one Se+1.33- atom. The Se–Se bond length is 2.55 Å. In the second Se+1.33- site, Se+1.33- is bonded in a 6-coordinate geometry to six La3+ atoms. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four La3+ atoms to form a mixture of edge and corner-sharing OLa4 tetrahedra. In the second O2- site, O2- is bonded to four La3+ atoms to form a mixture of edge and corner-sharing OLa4 tetrahedra. In the third O2- site, O2- is bonded to four La3+ atoms to form a mixture of edge and corner-sharing OLa4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La2SeO2 by Materials Project

La2SeO2 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. La3+ is bonded in a 4-coordinate geometry to three equivalent Se2- and four equivalent O2- atoms. All La–Se bond lengths are 3.15 Å. There are one shorter (2.41 Å) and three longer (2.45 Å) La–O bond lengths. Se2- is bonded to six equivalent La3+ atoms to form distorted SeLa6 octahedra that share corners with twelve equivalent OLa4 tetrahedra, edges with six equivalent SeLa6 octahedra, and edges with six equivalent OLa4 tetrahedra. O2- is bonded to four equivalent La3+ atoms to form OLa4 tetrahedra that share corners with six equivalent SeLa6 octahedra, corners with six equivalent OLa4 tetrahedra, edges with three equivalent SeLa6 octahedra, and edges with three equivalent OLa4 tetrahedra. The corner-sharing octahedra tilt angles range from 26–49°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La2Se2O by Materials Project

La2Se2O crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 1-coordinate geometry to six Se2- and one O2- atom. There are a spread of La–Se bond distances ranging from 3.00–3.16 Å. The La–O bond length is 2.42 Å. In the second La3+ site, La3+ is bonded in a 7-coordinate geometry to three Se2- and three equivalent O2- atoms. There are a spread of La–Se bond distances ranging from 3.06–3.19 Å. There are one shorter (2.44 Å) and two longer (2.47 Å) La–O bond lengths. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to five La3+ atoms. In the second Se2- site, Se2- is bonded in a 4-coordinate geometry to four La3+ atoms. O2- is bonded to four La3+ atoms to form a mixture of edge and corner-sharing OLa4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La(SeO3)2 by Materials Project

La(SeO3)2 crystallizes in the orthorhombic Pca2_1 space group. The structure is two-dimensional and consists of two La(SeO3)2 sheets oriented in the (0, 0, 1) direction. there are two inequivalent La2+ sites. In the first La2+ site, La2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of La–O bond distances ranging from 2.51–2.80 Å. In the second La2+ site, La2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of La–O bond distances ranging from 2.48–2.85 Å. There are four inequivalent Se5+ sites. In the first Se5+ site, Se5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.71–1.78 Å. In the second Se5+ site, Se5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.71–1.77 Å. In the third Se5+ site, Se5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.67–1.73 Å. In the fourth Se5+ site, Se5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.68–1.74 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three La2+ and one Se5+ atom. In the second O2- site, O2- is bonded in a distorted water-like geometry to one La2+ and one Se5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two La2+ and one Se5+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Se5+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three La2+ and one Se5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two La2+ and one Se5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent La2+ and one Se5+ atom. In the eighth O2- site, O2- is bonded in a distorted water-like geometry to one La2+ and one Se5+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent La2+ and one Se5+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to two La2+ and one Se5+ atom. In the eleventh O2- site, O2- is bonded in a single-bond geometry to one Se5+ atom. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to two La2+ and one Se5+ atom.

36 MATERIALS SCIENCE↗