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Materials Data on La2Cu(SeO3)4 by Materials Project

La2Cu(SeO3)4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. La3+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of La–O bond distances ranging from 2.51–2.96 Å. Cu2+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.94 Å) and two longer (1.97 Å) Cu–O bond length. There are two inequivalent Se4+ sites. In the first Se4+ site, Se4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.71–1.76 Å. In the second Se4+ site, Se4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.73 Å) and one longer (1.76 Å) Se–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one La3+, one Cu2+, and one Se4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three equivalent La3+ and one Se4+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent La3+ and one Se4+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent La3+ and one Se4+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent La3+ and one Se4+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one Cu2+ and one Se4+ atom.

36 MATERIALS SCIENCE↗

Materials Data on LaCuSeO by Materials Project

LaCuOSe is Parent of FeAs superconductors structured and crystallizes in the tetragonal P4/nmm space group. The structure is two-dimensional and consists of one CuSe sheet oriented in the (0, 0, 1) direction and one LaO sheet oriented in the (0, 0, 1) direction. In the CuSe sheet, Cu1+ is bonded to four equivalent Se2- atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. All Cu–Se bond lengths are 2.52 Å. Se2- is bonded in a 4-coordinate geometry to four equivalent Cu1+ atoms. In the LaO sheet, La3+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All La–O bond lengths are 2.38 Å. O2- is bonded to four equivalent La3+ atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra.

36 MATERIALS SCIENCE↗

Materials Data on La4Cu3SeO12 by Materials Project

La4Cu3SeO12 is (Cubic) Perovskite-derived structured and crystallizes in the cubic Im-3m space group. The structure is three-dimensional. La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with twelve equivalent LaO12 cuboctahedra, faces with six equivalent LaO12 cuboctahedra, faces with two equivalent SeO6 octahedra, and faces with six equivalent CuO6 octahedra. All La–O bond lengths are 2.77 Å. Cu2+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with two equivalent SeO6 octahedra, corners with four equivalent CuO6 octahedra, and faces with eight equivalent LaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.96 Å) and two longer (2.09 Å) Cu–O bond lengths. Se6+ is bonded to six equivalent O2- atoms to form SeO6 octahedra that share corners with six equivalent CuO6 octahedra and faces with eight equivalent LaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Se–O bond lengths are 1.83 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four equivalent La3+ and two equivalent Cu2+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four equivalent La3+, one Cu2+, and one Se6+ atom.

36 MATERIALS SCIENCE↗

Materials Data on La2CuSe2O by Materials Project

La2CuSe2O crystallizes in the tetragonal P4/mmm space group. The structure is one-dimensional and consists of one La2CuSe2O ribbon oriented in the (0, 0, 1) direction. La+2.50+ is bonded in a linear geometry to one Se2- and one O2- atom. The La–Se bond length is 2.83 Å. The La–O bond length is 2.12 Å. Cu1+ is bonded in a linear geometry to two equivalent Se2- atoms. Both Cu–Se bond lengths are 2.22 Å. Se2- is bonded in a linear geometry to one La+2.50+ and one Cu1+ atom. O2- is bonded in a linear geometry to two equivalent La+2.50+ atoms.

36 MATERIALS SCIENCE↗