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Materials Data on Ba2Y(CuO2)3 by Materials Project

YBa2Cu3O6 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.76–3.26 Å. In the second Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are six shorter (2.76 Å) and two longer (3.19 Å) Ba–O bond lengths. Y3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Y–O bond distances ranging from 2.21–2.50 Å. There are three inequivalent Cu+1.67+ sites. In the first Cu+1.67+ site, Cu+1.67+ is bonded to five O2- atoms to form corner-sharing CuO5 trigonal bipyramids. There are a spread of Cu–O bond distances ranging from 1.96–2.32 Å. In the second Cu+1.67+ site, Cu+1.67+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are two shorter (1.99 Å) and one longer (2.09 Å) Cu–O bond lengths. In the third Cu+1.67+ site, Cu+1.67+ is bonded in a square co-planar geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.91–1.98 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to four Ba2+ and two equivalent Cu+1.67+ atoms to form a mixture of distorted face, edge, and corner-sharing OBa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 1–65°. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Y3+, and two equivalent Cu+1.67+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Y3+, and two equivalent Cu+1.67+ atoms. In the fourth O2- site, O2- is bonded in a distorted see-saw-like geometry to two equivalent Ba2+, two equivalent Y3+, and two equivalent Cu+1.67+ atoms. In the fifth O2- site, O2- is bonded to four equivalent Ba2+ and two Cu+1.67+ atoms to form a mixture of distorted face, edge, and corner-sharing OBa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–65°. In the sixth O2- site, O2- is bonded to four equivalent Ba2+ and two Cu+1.67+ atoms to form a mixture of distorted face, edge, and corner-sharing OBa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–60°.

36 MATERIALS SCIENCE↗

Materials Data on Al2(CuO2)3 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Materials Data on Ca4(CuO2)5 by Materials Project

Ca4Cu5O10 crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.60 Å. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form edge-sharing CaO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.36–2.42 Å. There are three inequivalent Cu+2.40+ sites. In the first Cu+2.40+ site, Cu+2.40+ is bonded in a square co-planar geometry to four O2- atoms. All Cu–O bond lengths are 1.87 Å. In the second Cu+2.40+ site, Cu+2.40+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There is two shorter (1.90 Å) and two longer (1.91 Å) Cu–O bond length. In the third Cu+2.40+ site, Cu+2.40+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There is three shorter (1.95 Å) and one longer (1.96 Å) Cu–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Ca2+ and two equivalent Cu+2.40+ atoms to form a mixture of distorted edge and corner-sharing OCa2Cu2 trigonal pyramids. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Cu+2.40+ atoms. In the third O2- site, O2- is bonded in a 5-coordinate geometry to three Ca2+ and two Cu+2.40+ atoms. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to three Ca2+ and two Cu+2.40+ atoms. In the fifth O2- site, O2- is bonded to two equivalent Ca2+ and two equivalent Cu+2.40+ atoms to form a mixture of distorted edge and corner-sharing OCa2Cu2 trigonal pyramids. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Cu+2.40+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Li3(CuO2)2 by Materials Project

Li3Cu2O4 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two equivalent LiO4 tetrahedra and edges with two equivalent LiO5 square pyramids. There are a spread of Li–O bond distances ranging from 1.91–1.98 Å. In the second Li1+ site, Li1+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.93–2.11 Å. In the third Li1+ site, Li1+ is bonded to five O2- atoms to form distorted LiO5 square pyramids that share edges with two equivalent LiO5 square pyramids and edges with two equivalent LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 2.07–2.32 Å. There are two inequivalent Cu+2.50+ sites. In the first Cu+2.50+ site, Cu+2.50+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.90 Å) and two longer (1.91 Å) Cu–O bond length. In the second Cu+2.50+ site, Cu+2.50+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.90 Å) and two longer (1.91 Å) Cu–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to three Li1+ and two equivalent Cu+2.50+ atoms to form OLi3Cu2 square pyramids that share corners with three equivalent OLi4Cu2 octahedra, corners with six OLi3Cu2 trigonal bipyramids, edges with two equivalent OLi3Cu2 square pyramids, and edges with two OLi3Cu2 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 44–77°. In the second O2- site, O2- is bonded to three Li1+ and two equivalent Cu+2.50+ atoms to form distorted OLi3Cu2 trigonal bipyramids that share corners with two equivalent OLi4Cu2 octahedra, corners with two equivalent OLi3Cu2 square pyramids, a cornercorner with one OLi3Cu2 trigonal bipyramid, edges with three equivalent OLi4Cu2 octahedra, an edgeedge with one OLi3Cu2 square pyramid, and edges with two equivalent OLi3Cu2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 2°. In the third O2- site, O2- is bonded to three Li1+ and two equivalent Cu+2.50+ atoms to form distorted OLi3Cu2 trigonal bipyramids that share corners with four equivalent OLi3Cu2 square pyramids, a cornercorner with one OLi3Cu2 trigonal bipyramid, edges with two equivalent OLi4Cu2 octahedra, an edgeedge with one OLi3Cu2 square pyramid, and edges with two equivalent OLi3Cu2 trigonal bipyramids. In the fourth O2- site, O2- is bonded to four Li1+ and two equivalent Cu+2.50+ atoms to form distorted OLi4Cu2 octahedra that share corners with three equivalent OLi3Cu2 square pyramids, corners with two equivalent OLi3Cu2 trigonal bipyramids, edges with two equivalent OLi4Cu2 octahedra, and edges with five OLi3Cu2 trigonal bipyramids.

36 MATERIALS SCIENCE↗

Materials Data on Ca(CuO2)2 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Materials Data on Li3Cr(CuO2)4 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Materials Data on Ba2(CuO2)3 by Materials Project

Ba2Cu3O6 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. Ba2+ is bonded in a distorted hexagonal planar geometry to six O2- atoms. There are a spread of Ba–O bond distances ranging from 2.61–2.80 Å. There are three inequivalent Cu+2.67+ sites. In the first Cu+2.67+ site, Cu+2.67+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.82 Å) and two longer (1.86 Å) Cu–O bond length. In the second Cu+2.67+ site, Cu+2.67+ is bonded in a linear geometry to two equivalent O2- atoms. Both Cu–O bond lengths are 1.73 Å. In the third Cu+2.67+ site, Cu+2.67+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.83 Å) and two longer (1.85 Å) Cu–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two Cu+2.67+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+ and one Cu+2.67+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two Cu+2.67+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Ba2Pr(CuO2)3 by Materials Project

PrBa2Cu3O6 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.84 Å) and four longer (2.93 Å) Ba–O bond lengths. Pr3+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Pr–O bond lengths are 2.51 Å. There are two inequivalent Cu+1.67+ sites. In the first Cu+1.67+ site, Cu+1.67+ is bonded to five O2- atoms to form corner-sharing CuO5 square pyramids. There are four shorter (1.97 Å) and one longer (2.61 Å) Cu–O bond lengths. In the second Cu+1.67+ site, Cu+1.67+ is bonded in a linear geometry to two equivalent O2- atoms. Both Cu–O bond lengths are 1.81 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Pr3+, and two equivalent Cu+1.67+ atoms. In the second O2- site, O2- is bonded in a 1-coordinate geometry to four equivalent Ba2+ and two Cu+1.67+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Ba2Pr(CuO2)3 by Materials Project

PrBa2Cu3O6 crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.79 Å) and four longer (2.81 Å) Ba–O bond lengths. In the second Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.79 Å) and four longer (2.81 Å) Ba–O bond lengths. Pr3+ is bonded to four equivalent O2- atoms to form corner-sharing PrO4 tetrahedra. All Pr–O bond lengths are 2.29 Å. There are two inequivalent Cu+1.67+ sites. In the first Cu+1.67+ site, Cu+1.67+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.83 Å) and two longer (2.13 Å) Cu–O bond length. In the second Cu+1.67+ site, Cu+1.67+ is bonded in a distorted rectangular see-saw-like geometry to six O2- atoms. There are four shorter (1.92 Å) and two longer (2.76 Å) Cu–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to four equivalent Ba2+ and two Cu+1.67+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two equivalent Cu+1.67+ atoms. In the third O2- site, O2- is bonded to two equivalent Pr3+ and two equivalent Cu+1.67+ atoms to form corner-sharing OPr2Cu2 tetrahedra.

36 MATERIALS SCIENCE↗

Materials Data on Zn(CuO2)2 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Materials Data on Al(CuO2)2 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Materials Data on Co(CuO2)4 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Materials Data on Co(CuO2)4 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Materials Data on Ba2Gd(CuO2)4 by Materials Project

GdBa2Cu4O8 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Ba2+ is bonded in a distorted q6 geometry to ten O2- atoms. There are four shorter (2.78 Å) and six longer (2.99 Å) Ba–O bond lengths. Gd3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.42 Å) and four longer (2.43 Å) Gd–O bond lengths. There are two inequivalent Cu+2.25+ sites. In the first Cu+2.25+ site, Cu+2.25+ is bonded to five O2- atoms to form corner-sharing CuO5 square pyramids. There are four shorter (1.97 Å) and one longer (2.29 Å) Cu–O bond lengths. In the second Cu+2.25+ site, Cu+2.25+ is bonded in a square co-planar geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.84–1.96 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Ba2+ and two Cu+2.25+ atoms to form a mixture of distorted edge and corner-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 11°. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Gd3+, and two equivalent Cu+2.25+ atoms. In the third O2- site, O2- is bonded in a distorted T-shaped geometry to two equivalent Ba2+ and three equivalent Cu+2.25+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Gd3+, and two equivalent Cu+2.25+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on BaCa2Cu3O5 by Materials Project

Ba2Ca4(CuO2)5Cu crystallizes in the tetragonal P4/mmm space group. The structure is two-dimensional and consists of one cuprum molecule and one Ba2Ca4(CuO2)5 sheet oriented in the (0, 0, 1) direction. In the Ba2Ca4(CuO2)5 sheet, Ba2+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All Ba–O bond lengths are 2.61 Å. There are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.52 Å) and four longer (2.56 Å) Ca–O bond lengths. In the second Ca2+ site, Ca2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.47 Å) and four longer (2.62 Å) Ca–O bond lengths. There are three inequivalent Cu+1.33+ sites. In the first Cu+1.33+ site, Cu+1.33+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.98 Å. In the second Cu+1.33+ site, Cu+1.33+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.97 Å. In the third Cu+1.33+ site, Cu+1.33+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.97 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Ba2+, two equivalent Ca2+, and two equivalent Cu+1.33+ atoms to form distorted OBa2Ca2Cu2 octahedra that share corners with eight OCa4Cu2 octahedra, edges with three OCa4Cu2 octahedra, and faces with four equivalent OBa2Ca2Cu2 octahedra. The corner-sharing octahedra tilt angles range from 4–67°. In the second O2- site, O2- is bonded to four Ca2+ and two equivalent Cu+1.33+ atoms to form a mixture of face, edge, and corner-sharing OCa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 1–67°. In the third O2- site, O2- is bonded to four equivalent Ca2+ and two equivalent Cu+1.33+ atoms to form a mixture of face, edge, and corner-sharing OCa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–67°.

36 MATERIALS SCIENCE↗

Superconductivity above 90 K in the square-planar compound system ABa2Cu3O(6 + x) with A = Y, La, Nd, Sm, Eu, Gd, Ho, Er, and Lu

Superconductivity has been found in the 90-K range in ABa2Cu3O(6 + x) with A = La, Nd, Sm, Eu, Gd, Ho, Er, and Lu in addition to Y. The results suggest that the unique square-planar Cu atoms, each surrounded by four or six oxygen atoms, are crucial to the superconductivity of oxides in general. In particular, the high Tc of ABa2Cu3O(6 + x) is attributed mainly to the quasi-two-dimensional assembly of the CuO2-Ba-CuO(2 + x)Ba-CuO2 layers sandwiched between two A layers, with particular emphasis in the CuO(2 + x) layers. Higher-Tc oxides are predicted for compounds with bigger assemblies of CuO2 layers coupled by Ba layers.

Hor, P. H.↗

Structure of Charge Density Waves in La1.875Ba0.125CuO4

Although charge-density wave (CDW) correlations exist in several families of cuprate superconductors, they exhibit substantial variation in CDW wavevector and correlation length, indicating a key role for CDW-lattice interactions. We investigated this interaction in La1.875Ba0.125CuO4 using single crystal x-ray diffraction to collect a large number of CDW peak intensities, and determined the Cu and La/Ba atomic distortions induced by the formation of CDW order. Within the CuO2 planes, the distortions involve a periodic modulation of the Cu-Cu spacing along the direction of the ordering wave vector. The charge ordering within the copper-oxygen layer induces an out-of-plane breathing modulation of the surrounding lanthanum layers, which leads to a related distortion on the adjacent copper-oxygen layer. Our result implies that the CDW-related structural distortions do not remain confined to a single layer but rather propagate an appreciable distance through the crystal. This leads to overlapping structural modulations, in which CuO2 planes exhibit distortions arising from the orthogonal CDWs in adjacent layers as well as distortions from the CDW within the layer itself. We attribute this striking effect to the weak c-axis charge screening in cuprates and suggest this effect could help couple the CDW between adjacent planes in the crystal.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Preparation and characteristics of superconducting cuprate thin films: Nd(2-x)Ce(x)CuO4 and substituted Bi-system

Characteristics of the electron-doped-type Nd(2-x)Ce(x)CuO4 systems and substituted Bi2(Sr,Ln)3Cu2Oy system were systematically studied using the high quality thin-film samples. The Nd(2-x)Ce(x)CuO4 thin films with various Ce concentrations, x, were prepared by RF magnetron sputtering on SrTiO3 heated at around 500 C. After subsequent annealing at 1100 C in air, the films showed the c-axis orientation normal to the substrates. By means of the reducing treatment (annealing in a vacuum), superconductivity was induced for the films with 0.14 is less than or equal to x is less than or equal to 0.18. The superconductivity and transport properties of the films were strongly affected by the reducing treatment. The x = 0.15 film exhibited a sharp superconducting transition with zero resistivity at 22 K, in consistent with the diamagnetic properties. The resistivity of the films was fairly low with metallic characteristics, and the sight of the Hall coefficient was negative in the normal state. On the other hand, the normal-state optical measurements showed that the undoped Nd2CuO4 is a semiconductor with a charge transfer gap of 1.3 eV, and that, when Ce ions were doped, a plasma reflection due to the free-carriers came to be seen with the plasma frequency of 1.07 eV for 0.14 is less than or equal to x is less than or equal to 0.18. Moreover, x ray photoemission study revealed that the Cu valence of the film decreased for 2(+) for x = 0 to 1(+) for x = 0.15. These physical properties are in contrast with those of hole-doped-type cuprate superconductors. Bi2(Sr,Ln)3Cu2Oy thin films were also prepared on MgO substrates heated at 600 to 700 C by similar methods. It was found that the growth conditions for Bi-systems with two CuO2 planes were different for each composition and species of lanthanoid in the films. Moreover, preparation of Bi-system with three CuO2 planes was very difficult when lanthanoid atoms were doped in the system. Their electric transport properties and x ray photoemission spectroscopy were investigated. Carrier concentration and Cu valence were discussed with regard to the superconductivity.

Adachi, H.↗