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At least 127 records · Page 7

Materials Data on Ba(CuO)2 by Materials Project

BaCu2O2 crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. Ba2+ is bonded to six equivalent O2- atoms to form a mixture of edge and corner-sharing BaO6 octahedra. The corner-sharing octahedral tilt angles are 5°. There are two shorter (2.66 Å) and four longer (2.90 Å) Ba–O bond lengths. Cu1+ is bonded in a linear geometry to two equivalent O2- atoms. Both Cu–O bond lengths are 1.85 Å. O2- is bonded to three equivalent Ba2+ and two equivalent Cu1+ atoms to form a mixture of distorted edge and corner-sharing OBa3Cu2 trigonal bipyramids.

36 MATERIALS SCIENCE↗

Materials Data on Li(CuO)3 by Materials Project

LiCu3O3 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Li1+ is bonded to five O2- atoms to form distorted corner-sharing LiO5 trigonal bipyramids. There are four shorter (2.04 Å) and one longer (2.13 Å) Li–O bond lengths. There are three inequivalent Cu+1.67+ sites. In the first Cu+1.67+ site, Cu+1.67+ is bonded in a linear geometry to two equivalent O2- atoms. Both Cu–O bond lengths are 1.86 Å. In the second Cu+1.67+ site, Cu+1.67+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.99 Å. In the third Cu+1.67+ site, Cu+1.67+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.98 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Li1+ and three Cu+1.67+ atoms to form distorted OLi2Cu3 trigonal bipyramids that share corners with two equivalent OLiCu4 square pyramids, corners with five equivalent OLi2Cu3 trigonal bipyramids, and edges with four equivalent OLi2Cu3 trigonal bipyramids. In the second O2- site, O2- is bonded to one Li1+ and four equivalent Cu+1.67+ atoms to form distorted OLiCu4 square pyramids that share corners with four equivalent OLiCu4 square pyramids, corners with four equivalent OLi2Cu3 trigonal bipyramids, and edges with four equivalent OLiCu4 square pyramids.

36 MATERIALS SCIENCE↗

Materials Data on Ca(CuO)2 by Materials Project

CaCu2O2 crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. Ca2+ is bonded to six equivalent O2- atoms to form a mixture of edge and corner-sharing CaO6 octahedra. The corner-sharing octahedral tilt angles are 5°. There are two shorter (2.27 Å) and four longer (2.67 Å) Ca–O bond lengths. Cu1+ is bonded in a linear geometry to two equivalent O2- atoms. Both Cu–O bond lengths are 1.86 Å. O2- is bonded to three equivalent Ca2+ and two equivalent Cu1+ atoms to form a mixture of distorted edge and corner-sharing OCa3Cu2 trigonal bipyramids.

36 MATERIALS SCIENCE↗

Materials Data on Li(CuO)3 by Materials Project

LiCu3O3 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to five O2- atoms to form distorted corner-sharing LiO5 trigonal bipyramids. There are four shorter (2.04 Å) and one longer (2.11 Å) Li–O bond lengths. In the second Li1+ site, Li1+ is bonded to five O2- atoms to form distorted LiO5 trigonal bipyramids that share corners with five equivalent LiO5 trigonal bipyramids and edges with four equivalent CuO5 square pyramids. There are four shorter (2.05 Å) and one longer (2.23 Å) Li–O bond lengths. There are five inequivalent Cu+1.67+ sites. In the first Cu+1.67+ site, Cu+1.67+ is bonded in a linear geometry to two O2- atoms. Both Cu–O bond lengths are 1.86 Å. In the second Cu+1.67+ site, Cu+1.67+ is bonded in a distorted square co-planar geometry to four O2- atoms. All Cu–O bond lengths are 1.98 Å. In the third Cu+1.67+ site, Cu+1.67+ is bonded in a distorted square co-planar geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.99 Å. In the fourth Cu+1.67+ site, Cu+1.67+ is bonded to five O2- atoms to form distorted CuO5 square pyramids that share corners with five equivalent CuO5 square pyramids and edges with four equivalent LiO5 trigonal bipyramids. There are four shorter (1.98 Å) and one longer (2.68 Å) Cu–O bond lengths. In the fifth Cu+1.67+ site, Cu+1.67+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.98 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Li1+ and three Cu+1.67+ atoms to form distorted OLi2Cu3 trigonal bipyramids that share corners with two equivalent OLiCu4 square pyramids, corners with five OLi2Cu3 trigonal bipyramids, and edges with four equivalent OLi2Cu3 trigonal bipyramids. In the second O2- site, O2- is bonded to two equivalent Li1+ and three Cu+1.67+ atoms to form distorted OLi2Cu3 trigonal bipyramids that share corners with four OCu6 octahedra, corners with five OLi2Cu3 trigonal bipyramids, and edges with four equivalent OLi2Cu3 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 76–88°. In the third O2- site, O2- is bonded to six Cu+1.67+ atoms to form distorted OCu6 octahedra that share corners with four equivalent OCu6 octahedra, corners with eight equivalent OLi2Cu3 trigonal bipyramids, and edges with four equivalent OLi2Cu4 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded to one Li1+ and four equivalent Cu+1.67+ atoms to form OLiCu4 square pyramids that share corners with four equivalent OLiCu4 square pyramids, corners with four equivalent OLi2Cu3 trigonal bipyramids, and edges with four equivalent OLiCu4 square pyramids. In the fifth O2- site, O2- is bonded to two equivalent Li1+ and four equivalent Cu+1.67+ atoms to form OLi2Cu4 octahedra that share corners with four equivalent OLi2Cu4 octahedra, corners with eight equivalent OLi2Cu3 trigonal bipyramids, and edges with four equivalent OCu6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗

Materials Data on Li(CuO)3 by Materials Project

LiCu3O3 crystallizes in the tetragonal P4mm space group. The structure is three-dimensional. Li1+ is bonded to five O2- atoms to form LiO5 square pyramids that share a cornercorner with one CuO5 square pyramid, corners with four equivalent LiO5 square pyramids, edges with four equivalent LiO5 square pyramids, and edges with four equivalent CuO5 square pyramids. There are four shorter (2.03 Å) and one longer (2.25 Å) Li–O bond lengths. There are three inequivalent Cu+1.67+ sites. In the first Cu+1.67+ site, Cu+1.67+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.80 Å) and one longer (1.89 Å) Cu–O bond length. In the second Cu+1.67+ site, Cu+1.67+ is bonded to five O2- atoms to form CuO5 square pyramids that share a cornercorner with one LiO5 square pyramid, corners with eight CuO5 square pyramids, and edges with four equivalent CuO5 square pyramids. There are four shorter (2.04 Å) and one longer (2.37 Å) Cu–O bond lengths. In the third Cu+1.67+ site, Cu+1.67+ is bonded to five O2- atoms to form distorted CuO5 square pyramids that share corners with eight CuO5 square pyramids, edges with four equivalent LiO5 square pyramids, and edges with four equivalent CuO5 square pyramids. There are four shorter (2.03 Å) and one longer (2.24 Å) Cu–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Li1+ and two Cu+1.67+ atoms to form distorted OLi4Cu2 octahedra that share corners with four equivalent OLi4Cu2 octahedra, a cornercorner with one OCu5 square pyramid, and edges with eight OLi4Cu2 octahedra. The corner-sharing octahedral tilt angles are 13°. In the second O2- site, O2- is bonded to five Cu+1.67+ atoms to form distorted OCu5 square pyramids that share corners with five OLi4Cu2 octahedra, corners with four equivalent OCu5 square pyramids, and edges with four equivalent OCu5 square pyramids. The corner-sharing octahedra tilt angles range from 0–83°. In the third O2- site, O2- is bonded to one Li1+ and five Cu+1.67+ atoms to form OLiCu5 octahedra that share corners with four equivalent OLiCu5 octahedra, corners with four equivalent OCu5 square pyramids, and edges with eight OLi4Cu2 octahedra. The corner-sharing octahedral tilt angles are 13°.

36 MATERIALS SCIENCE↗

Materials Data on Li(CuO)3 by Materials Project

LiCu3O3 crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Li1+ is bonded to six equivalent O2- atoms to form corner-sharing LiO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Li–O bond lengths are 2.03 Å. Cu+1.67+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Cu–O bond lengths are 2.03 Å. O2- is bonded to two equivalent Li1+ and four equivalent Cu+1.67+ atoms to form a mixture of edge and corner-sharing OLi2Cu4 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗

Effect of redox promoters (CeO x and CuO x ) and surface sulfates on the selective catalytic reduction (SCR) of NO with NH 3 by supported V 2 O 5 -WO 3 /TiO 2 catalysts

A series of TiO 2 -supported MO x catalysts (M=V, W, Ce, Cu and S) were investigated for their SCR activity. In situ Raman spectroscopy indicated that the supported MO x phases were completely dispersed as surface sites on the TiO 2 support. In situ IR revealed that surface VO x , WO x and SO x sites anchored at both CeO x /CuO x and TiO 2 sites. The number of surface Lewis acid sites decreased with the addition of basic (CeO x /CuO x ) and acidic (VO x /WO x ) sites in all catalysts, and acidic SO x in the unpromoted and Ce-promoted catalysts. The surface VO x , WO x and SO x sites introduced surface Brønsted acid sites. The redox promoters increased the NO conversion, but SO x impregnation inhibited their effect due to acid (SO x )-base (CeO x /CuO x ) interactions. Finally, the SCR reaction was shown to efficiently proceed via either surface NH 3 * or NH 4 +* species, resolving the long-standing dispute on the involvement of these species in the SCR reaction.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Spin Polarization Enhanced Ethanol Selectivity in Electrocatalytic CO 2 Reduction on the Paramagnetic CuO Surface

We report an electrochemical CO 2 reduction reaction catalyzed by a paramagnetic and conductive CuO/Cu interface with spins polarized by a moderate external magnetic field (MF) of similar to 800 gauss, achieving a similar to 30% increase in CO 2 -to-C 2+ Faradaic efficiency (FE) compared to that in the absence of the MF in a flow cell electrolyzer. At a current density of 400 mA/cm 2 , the CO 2 -to-C 2+ FE reached 86.7 ± 2.7% with 47.9 ± 1.4% cathodic energy efficiency (EE) in contrast to the CO 2 -to-C 2+ FE of 67.6% with 36.4% of EE in the absence of MF. Notably, ethanol production exhibits a much higher response to the MF (similar to 55.6% increase in FE) than ethylene (similar to 6.4% increase in FE) at 400 mA/cm 2 . In situ surface-enhanced Raman spectroscopy (SERS) captured magnetic-field-enhanced *CO coverage and ethanol-forming C 2 intermediates on CuO/Cu, providing direct spectroscopic evidence of spin-modulated pathway selection. Here, computational study suggests that the enhancement of ethanol selectivity is due to the reduced reaction kinetic barrier under MF, while the ethylene selectivity is less affected, mainly due to the insensitivity of the kinetic barriers under MF.

10 SYNTHETIC FUELS↗

Anomalous lattice relaxation dynamics in optimally doped La 2−𝑥⁢ Sr 𝑥 ⁢CuO 4

The atomic lattice plays a critical role in the emergence of high-𝑇 𝑐 superconductivity in cuprates. While the dynamics associated with electron-lattice coupling typically unfold on picosecond-to-femtosecond timescales, we present an x-ray photon correlation spectroscopy investigation on an optimally doped La-based cuprate that reveals a strong response of kilosecond-scale lattice relaxation dynamics to the superconducting state. Notably, an anomaly emerges around 𝑇 𝑐 : upon cooling into the superconducting state, the average atomic relaxation lifetime decreases, i.e., dynamics accelerate. This indicates a significant change in the local disorder-induced strain field dynamics at the superconducting transition, highlighting a remarkable coupling between superconductivity and the lattice on quasistatic timescales.

Petsch, A. N. [SLAC National Accelerator Laborator↗

Scanning SQUID characterization of extremely overdoped La 2-x Sr x CuO 4

Recently, advances in film synthesis methods have enabled a study of extremely overdoped La 2 - x Sr x Cu O 4 . This has revealed a surprising behavior of the superfluid density as a function of doping and temperature, the explanation of which is vividly debated. One popular class of models posits electronic phase separation, where the superconducting phase fraction decreases with doping, while some competing phase (e.g., ferromagnetic) progressively takes over. A problem with this scenario is that all the way up to the dome edge the superconducting transition remains sharp, according to mutual inductance measurements. However, the physically relevant scale is the Pearl penetration depth Λ P , and this technique probes the sample on a length scale L that is much larger than Λ P . In the present paper, we use local scanning superconducting quantum interference device (SQUID) measurements that probe the susceptibility of the sample on the scale L << Λ P . Our SQUID maps show uniform landscapes of susceptibility and excellent overall agreement of the local penetration depth data with the bulk measurements. Overall, these results contribute an important piece to the puzzle of how high-temperature superconductivity vanishes on the overdoped side of the cuprate phase diagram.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗