Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “K edge”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 559 records · Page 31
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on K(Cu2Sb)2 by Materials Project

K(Cu2Sb)2 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. K1+ is bonded to six equivalent Sb3- atoms to form distorted edge-sharing KSb6 octahedra. All K–Sb bond lengths are 3.50 Å. There are two inequivalent Cu+1.25+ sites. In the first Cu+1.25+ site, Cu+1.25+ is bonded in a 4-coordinate geometry to four equivalent Sb3- atoms. There are one shorter (2.71 Å) and three longer (2.86 Å) Cu–Sb bond lengths. In the second Cu+1.25+ site, Cu+1.25+ is bonded in a trigonal non-coplanar geometry to three equivalent Sb3- atoms. All Cu–Sb bond lengths are 2.60 Å. Sb3- is bonded in a 10-coordinate geometry to three equivalent K1+ and seven Cu+1.25+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3Mg18Sn11 by Materials Project

K3Mg18Sn11 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 12-coordinate geometry to six Mg and six Sn atoms. All K–Mg bond lengths are 3.84 Å. There are three shorter (3.66 Å) and three longer (3.69 Å) K–Sn bond lengths. In the second K site, K is bonded to six equivalent Mg and six equivalent Sn atoms to form distorted KMg6Sn6 cuboctahedra that share corners with eighteen MgSn4 tetrahedra and edges with nine MgK2Sn4 tetrahedra. All K–Mg bond lengths are 3.84 Å. All K–Sn bond lengths are 3.69 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 5-coordinate geometry to five Sn atoms. There are a spread of Mg–Sn bond distances ranging from 2.97–3.09 Å. In the second Mg site, Mg is bonded to four Sn atoms to form distorted MgSn4 tetrahedra that share corners with two equivalent KMg6Sn6 cuboctahedra, corners with eleven MgSn4 tetrahedra, and edges with three MgK2Sn4 tetrahedra. There are a spread of Mg–Sn bond distances ranging from 2.89–3.04 Å. In the third Mg site, Mg is bonded to two equivalent K and four Sn atoms to form distorted MgK2Sn4 tetrahedra that share corners with twelve MgSn4 tetrahedra, an edgeedge with one KMg6Sn6 cuboctahedra, edges with six MgSn4 tetrahedra, and faces with two equivalent MgK2Sn4 tetrahedra. There are a spread of Mg–Sn bond distances ranging from 2.91–2.99 Å. In the fourth Mg site, Mg is bonded to two K and four Sn atoms to form distorted MgK2Sn4 tetrahedra that share a cornercorner with one KMg6Sn6 cuboctahedra, corners with twelve MgSn4 tetrahedra, an edgeedge with one KMg6Sn6 cuboctahedra, edges with six MgSn4 tetrahedra, and faces with two equivalent MgK2Sn4 tetrahedra. There are a spread of Mg–Sn bond distances ranging from 2.94–3.01 Å. There are three inequivalent Sn sites. In the first Sn site, Sn is bonded in a 6-coordinate geometry to six Mg atoms. In the second Sn site, Sn is bonded in a 9-coordinate geometry to two K and seven Mg atoms. In the third Sn site, Sn is bonded in a 9-coordinate geometry to two equivalent K and seven Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K2Hg(CN)4 by Materials Project

K2Hg(CN)4 crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. K1+ is bonded to six equivalent N3- atoms to form distorted edge-sharing KN6 octahedra. All K–N bond lengths are 2.97 Å. Hg2+ is bonded to four equivalent C2+ atoms to form HgC4 tetrahedra that share corners with four equivalent NK3C tetrahedra. All Hg–C bond lengths are 2.21 Å. C2+ is bonded in a single-bond geometry to one Hg2+ and one N3- atom. The C–N bond length is 1.17 Å. N3- is bonded to three equivalent K1+ and one C2+ atom to form distorted NK3C tetrahedra that share a cornercorner with one HgC4 tetrahedra, corners with nine equivalent NK3C tetrahedra, and edges with three equivalent NK3C tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3Mg18Pb11 by Materials Project

K3Mg18Pb11 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 12-coordinate geometry to six Pb atoms. There are three shorter (3.70 Å) and three longer (3.74 Å) K–Pb bond lengths. In the second K site, K is bonded to six equivalent Mg and six equivalent Pb atoms to form distorted KMg6Pb6 cuboctahedra that share corners with eighteen MgPb4 tetrahedra and edges with nine MgPb4 tetrahedra. All K–Mg bond lengths are 3.92 Å. All K–Pb bond lengths are 3.72 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 5-coordinate geometry to five Pb atoms. There are a spread of Mg–Pb bond distances ranging from 3.05–3.19 Å. In the second Mg site, Mg is bonded to four Pb atoms to form distorted MgPb4 tetrahedra that share corners with two equivalent KMg6Pb6 cuboctahedra, corners with eleven MgPb4 tetrahedra, and edges with three MgPb4 tetrahedra. There are a spread of Mg–Pb bond distances ranging from 2.93–3.11 Å. In the third Mg site, Mg is bonded to four Pb atoms to form MgPb4 tetrahedra that share corners with twelve MgPb4 tetrahedra, an edgeedge with one KMg6Pb6 cuboctahedra, and edges with four MgPb4 tetrahedra. There are one shorter (2.95 Å) and three longer (3.03 Å) Mg–Pb bond lengths. In the fourth Mg site, Mg is bonded to one K and four Pb atoms to form distorted MgKPb4 tetrahedra that share a cornercorner with one KMg6Pb6 cuboctahedra, corners with eleven MgPb4 tetrahedra, an edgeedge with one KMg6Pb6 cuboctahedra, and edges with seven MgPb4 tetrahedra. There are a spread of Mg–Pb bond distances ranging from 2.99–3.06 Å. There are three inequivalent Pb sites. In the first Pb site, Pb is bonded in a 6-coordinate geometry to six Mg atoms. In the second Pb site, Pb is bonded in a 9-coordinate geometry to two K and seven Mg atoms. In the third Pb site, Pb is bonded in a 9-coordinate geometry to two equivalent K and seven Mg atoms.

36 MATERIALS SCIENCE↗
NASA NTRS1974

The two-dimensional tunnel structures of K3Sb5O14 and K2Sb4O11

The structures of K3Sb5O14 and K2Sb4O11 have been solved by the single-crystal X-ray direct method and the heavy-atom method, respectively. The structure of K3Sb5O14 is orthorhombic, with space group Pbam and cell parameters a = 24.247 (4), b = 7.157 (2), c = 7.334 (2) A, Z = 4. The structure of K2Sb4O11 is monoclinic, with space group C2/m and cell parameters a = 19.473 (4), b = 7.542 (1), c = 7.198 (1) A, beta = 94.82 (2) deg, Z = 4. A full-matrix least-squares refinement gave R = 0.072 and R = 0.067, respectively. In both structures, oxygen atoms form an octahedron around each Sb atom and an irregular polyhedron around each K atom. By sharing corners and edges, the octahedra form a skeleton network having intersecting b-axis and c-axis tunnels. The K(+) ions, which have more than ten oxygen near neighbors, are located in these tunnels. Evidence for K(+)-ion transport within and between tunnels comes from ion exchange of the alkali ions in molten salts and anisotropic temperature factors that are anomalously large in the direction of the tunnels.

Hong, H. Y.-P.↗
NASA NTRS1991

Image feature extraction using Gabor-like transform

Noisy and highly textured images were operated on with a Gabor-like transform. The results were evaluated to see if useful features could be extracted using spatio-temporal operators. The use of spatio-temporal operators allows for extraction of features containing simultaneous frequency and orientation information. This method allows important features, both specific and generic, to be extracted from images. The transformation was applied to industrial inspection imagery, in particular, a NASA space shuttle main engine (SSME) system for offline health monitoring. Preliminary results are given and discussed. Edge features were extracted from one of the test images. Because of the highly textured surface (even after scan line smoothing and median filtering), the Laplacian edge operator yields many spurious edges.

Finegan, Michael K., Jr.↗
DOE OSTI2024

Density fluctuation statistics and turbulence spreading at the edge of L–mode plasmas

Long-wavelength density fluctuations ($k{\rho _i}$ <1) are studied using beam emission spectroscopy (BES) at the edge of DIII-D L-mode plasmas (ρ = 0.88–1.1) in scenarios with electron cyclotron heating (ECH) power ramp (P ECH up to 1.5 MW), neutral beam injection (NBI) power ramp (P NBI up to 2.5 MW), and injected torque scan (-1 < T inj <0.6 Nm). We find that broadband turbulent density fluctuations (ƒ ~ 20–120 kHz) have a non-Gaussian distribution. The skewness of $\delta n/n$ changes sign from negative at ρ < 0.95–0.97 to positive at ρ > 0.97, indicating the prevalence of density 'voids' at inner radii and density 'blobs' at outer radii and outside of the separatrix. The turbulence intensity flux $\left\langle {{{\tilde v}_{\text{r}}}{{\tilde n}^2}} \right\rangle$ is calculated to characterize turbulence spreading at the plasma edge. During ECH/NBI power ramps and at counter-I p injected torque, $\left\langle {{{\tilde v}_{\text{r}}}{{\tilde n}^2}} \right\rangle$ is directed inward inside the separatrix, which is evidence of inward spreading of turbulence intensity from the edge gradient region caused by the inner propagation of density 'voids'. Significantly weaker $\left\langle {{{\tilde v}_{\text{r}}}{{\tilde n}^2}} \right\rangle$ is observed with co-I p torque. A correlation between co-I p torque, turbulence intensity $\delta n/n$ at ρ = 0.97, and increased srape-off layer (SOL) heat flux decay length ${\lambda _q}$ is found in the torque scan scenario, showing that edge turbulence plays a material role in determining the SOL conditions and heat flux width.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2020

Partial equilibration of anti-Pfaffian edge modes at ν = 5 / 2

The thermal Hall conductance K of the fractional quantum Hall state at filling fraction ν = 5/2 has recently been measured to be K = 2.5π 2 $k$$^{2}_{B}$T/3h [M. Banerjee et al. Nature (London) 559, 205 (2018)]. Here, the half-integer value of this result (in units of π 2 $k$$^{2}_{B}$T/3h) provides strong evidence for the presence of a Majorana edge mode and a corresponding quantum Hall state hosting quasiparticles with non-Abelian statistics. Whether this measurement points to the realization of the PH-Pfaffian or the anti-Pfaffian state has been the subject of debate. Here we consider the implications of this measurement for anti-Pfaffian edge-state transport. We show that in the limit of strong Coulomb interaction and an approximate spin degeneracy in the lowest Landau level, the anti-Pfaffian state admits low-temperature edge phases that are consistent with the Hall conductance measurements. Furthermore, these edge phases can exhibit fully equilibrated electrical transport coexisting with partially equilibrated heat transport over a range of temperatures. Through a study of the kinetic equations describing low-temperature electrical and heat transport of these edge states, we determine regimes of parameter space, controlling the interactions between the different edge modes that agree with experiment.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K by Materials Project

K is Hg_xSn-like structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. K is bonded to eight equivalent K atoms to form a mixture of edge and corner-sharing KK8 hexagonal bipyramids. There are a spread of K–K bond distances ranging from 4.41–4.53 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K2MgFe(SiO3)8 by Materials Project

K2MgFe(SiO3)8 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded to twelve O atoms to form distorted KO12 cuboctahedra that share edges with six KO12 cuboctahedra and edges with twelve SiO4 tetrahedra. There are a spread of K–O bond distances ranging from 3.04–3.35 Å. In the second K site, K is bonded to twelve O atoms to form KO12 cuboctahedra that share edges with six KO12 cuboctahedra and edges with twelve SiO4 tetrahedra. There are a spread of K–O bond distances ranging from 3.04–3.26 Å. Mg is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Mg–O bond distances ranging from 1.95–2.30 Å. Fe is bonded to six O atoms to form distorted FeO6 octahedra that share corners with four SiO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.96–2.05 Å. There are eight inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one FeO6 octahedra, corners with three SiO4 tetrahedra, and edges with three KO12 cuboctahedra. The corner-sharing octahedral tilt angles are 44°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three SiO4 tetrahedra and edges with three KO12 cuboctahedra. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three SiO4 tetrahedra and edges with three KO12 cuboctahedra. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one FeO6 octahedra, corners with three SiO4 tetrahedra, and edges with three KO12 cuboctahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the fifth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one FeO6 octahedra, corners with three SiO4 tetrahedra, and edges with three KO12 cuboctahedra. The corner-sharing octahedral tilt angles are 47°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. In the sixth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three SiO4 tetrahedra and edges with three KO12 cuboctahedra. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the seventh Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one FeO6 octahedra, corners with three SiO4 tetrahedra, and edges with three KO12 cuboctahedra. The corner-sharing octahedral tilt angles are 44°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the eighth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three SiO4 tetrahedra and edges with three KO12 cuboctahedra. There are a spread of Si–O bond distances ranging from 1.59–1.67 Å. There are twenty-four inequivalent O sites. In the first O site, O is bonded in a distorted bent 150 degrees geometry to two equivalent K and two Si atoms. In the second O site, O is bonded in a distorted bent 150 degrees geometry to two equivalent K and two Si atoms. In the third O site, O is bonded in a distorted bent 120 degrees geometry to two K and two Si atoms. In the fourth O site, O is bonded in a distorted bent 120 degrees geometry to two K and two Si atoms. In the fifth O site, O is bonded in a distorted bent 120 degrees geometry to two equivalent K and two Si atoms. In the sixth O site, O is bonded in a distorted bent 120 degrees geometry to two equivalent K and two Si atoms. In the seventh O site, O is bonded in a 2-coordinate geometry to two K and two Si atoms. In the eighth O site, O is bonded in a distorted bent 150 degrees geometry to two K and two Si atoms. In the ninth O site, O is bonded in a 2-coordinate geometry to two K and two Si atoms. In the tenth O site, O is bonded in a distorted bent 120 degrees geometry to two K and two Si atoms. In the eleventh O site, O is bonded in a 2-coordinate geometry to two K and two Si atoms. In the twelfth O site, O is bonded in a 2-coordinate geometry to two K and two Si atoms. In the thirteenth O site, O is bonded in a single-bond geometry to one Fe atom. In the fourteenth O site, O is bonded in a single-bond geometry to one Mg atom. In the fifteenth O site, O is bonded in a single-bond geometry to one Fe atom. In the sixteenth O site, O is bonded in a single-bond geometry to one Mg atom. In the seventeenth O site, O is bonded in a distorted bent 150 degrees geometry to one Fe and one Si atom. In the eighteenth O site, O is bonded in a distorted bent 150 degrees geometry to one Mg and one Si atom. In the nineteenth O site, O is bonded in a distorted bent 150 degrees geometry to one Mg and one Si atom. In the twentieth O site, O is bonded in a distorted bent 120 degrees geometry to one Fe and one Si atom. In the twenty-first O site, O is bonded in a distorted bent 120 degrees geometry to one Fe and one Si atom. In the twenty-second O site, O is bonded in a distorted bent 120 degrees geometry to one Mg and one Si atom. In the twenty-third O site, O is bonded in a distorted bent 150 degrees geometry to one Fe and one Si atom. In the twenty-fourth O site, O is bonded in a distorted bent 150 degrees geometry to one Mg and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K4C2O9 by Materials Project

K4C2O9 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are three inequivalent K sites. In the first K site, K is bonded in a 6-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.79–3.13 Å. In the second K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.76–2.80 Å. In the third K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.75–3.09 Å. C is bonded in a trigonal planar geometry to three O atoms. There are a spread of C–O bond distances ranging from 1.28–1.31 Å. There are five inequivalent O sites. In the first O site, O is bonded to four K atoms to form a mixture of distorted edge and corner-sharing OK4 trigonal pyramids. In the second O site, O is bonded to four equivalent K atoms to form a mixture of distorted edge and corner-sharing OK4 trigonal pyramids. In the third O site, O is bonded in a distorted single-bond geometry to four K and one C atom. In the fourth O site, O is bonded in a distorted single-bond geometry to four K and one C atom. In the fifth O site, O is bonded in a single-bond geometry to two K and one C atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K7Rb5(Fe2O5)2 by Materials Project

Rb5K7(Fe2O5)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are five inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Rb–O bond distances ranging from 3.03–3.51 Å. In the second Rb1+ site, Rb1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Rb–O bond distances ranging from 3.04–3.51 Å. In the third Rb1+ site, Rb1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Rb–O bond distances ranging from 2.94–3.31 Å. In the fourth Rb1+ site, Rb1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Rb–O bond distances ranging from 2.94–3.31 Å. In the fifth Rb1+ site, Rb1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Rb–O bond distances ranging from 2.80–3.09 Å. There are seven inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to four O2- atoms to form distorted edge-sharing KO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.64–2.79 Å. In the second K1+ site, K1+ is bonded to four O2- atoms to form distorted edge-sharing KO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.63–2.78 Å. In the third K1+ site, K1+ is bonded to four O2- atoms to form distorted edge-sharing KO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.64–2.76 Å. In the fourth K1+ site, K1+ is bonded to four O2- atoms to form edge-sharing KO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.65–2.75 Å. In the fifth K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.75–3.09 Å. In the sixth K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.73–3.07 Å. In the seventh K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.73–3.06 Å. There are four inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.89 Å) and one longer (1.94 Å) Fe–O bond length. In the second Fe2+ site, Fe2+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of Fe–O bond distances ranging from 1.88–1.94 Å. In the third Fe2+ site, Fe2+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.89 Å) and one longer (1.95 Å) Fe–O bond length. In the fourth Fe2+ site, Fe2+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of Fe–O bond distances ranging from 1.88–1.94 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to two Rb1+, four K1+, and one Fe2+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three Rb1+, three K1+, and one Fe2+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Rb1+, three K1+, and one Fe2+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two Rb1+, four K1+, and one Fe2+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three Rb1+, three K1+, and one Fe2+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two Rb1+, four K1+, and one Fe2+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two Rb1+, four K1+, and one Fe2+ atom. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to three Rb1+, three K1+, and one Fe2+ atom. In the ninth O2- site, O2- is bonded in a 5-coordinate geometry to three Rb1+, one K1+, and two Fe2+ atoms. In the tenth O2- site, O2- is bonded in a 5-coordinate geometry to two Rb1+, two K1+, and two Fe2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3TaO2F7 by Materials Project

K3TaO2F7 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are three inequivalent K sites. In the first K site, K is bonded in a 6-coordinate geometry to six F atoms. There are a spread of K–F bond distances ranging from 2.60–3.13 Å. In the second K site, K is bonded in a 8-coordinate geometry to one O and seven F atoms. The K–O bond length is 2.97 Å. There are a spread of K–F bond distances ranging from 2.49–3.13 Å. In the third K site, K is bonded in a 6-coordinate geometry to one O and five F atoms. The K–O bond length is 3.02 Å. There are a spread of K–F bond distances ranging from 2.48–2.92 Å. Ta is bonded in a distorted pentagonal bipyramidal geometry to two O and five F atoms. Both Ta–O bond lengths are 2.12 Å. There are a spread of Ta–F bond distances ranging from 1.92–1.96 Å. There are two inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to one K, one Ta, and one O atom. The O–O bond length is 1.37 Å. In the second O site, O is bonded in a 3-coordinate geometry to one K, one Ta, and one O atom. There are seven inequivalent F sites. In the first F site, F is bonded in a distorted single-bond geometry to two K and one Ta atom. In the second F site, F is bonded in a distorted single-bond geometry to two K and one Ta atom. In the third F site, F is bonded in a distorted single-bond geometry to two K and one Ta atom. In the fourth F site, F is bonded in a distorted rectangular see-saw-like geometry to four K atoms. In the fifth F site, F is bonded to four K atoms to form distorted edge-sharing FK4 tetrahedra. In the sixth F site, F is bonded in a distorted trigonal non-coplanar geometry to two K and one Ta atom. In the seventh F site, F is bonded in a distorted single-bond geometry to two K and one Ta atom.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Orbital and spin character of doped carriers in infinite-layer nickelates

The recent discovery of superconductivity in Nd1-xSrxNiO2 has drawn significant attention in the field. A key open question regards the evolution of the electronic structure with respect to hole doping. Here we exploit x-ray absorption spectroscopy (XAS) and resonant inelastic x-ray scattering (RIXS) to probe the doping-dependent electronic structure of Nd1-xSrxNiO2. Upon doping, a high-energy feature in Ni L3-edge XAS develops in addition to the main absorption peak, while XAS at the O K-, Nd M3- and Nd M5-edge exhibits a much weaker response. This implies that doped holes are mainly introduced into Ni 3d states. By comparing our data to atomic multiplet calculations including D4h crystal field, the doping-induced feature in Ni L3-edge XAS is consistent with a d8 spin-singlet state in which doped holes reside in the 3dx2-y2 orbitals. This is further supported by the softening of RIXS orbital excitations due to doping, corroborating with the Fermi level shift associated with increasing holes in the Ni 3dx2-y2 orbital.

2-dimensional systems↗
DOE OSTI2020

Materials Data on K3HPdS2(ClO3)2 by Materials Project

K3PdHS2(O3Cl)2 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to six O2- and two equivalent Cl1- atoms. There are a spread of K–O bond distances ranging from 2.81–2.99 Å. There are one shorter (3.36 Å) and one longer (3.37 Å) K–Cl bond lengths. In the second K1+ site, K1+ is bonded to two equivalent O2- and four equivalent Cl1- atoms to form distorted edge-sharing KCl4O2 pentagonal pyramids. Both K–O bond lengths are 2.77 Å. There are two shorter (3.17 Å) and two longer (3.20 Å) K–Cl bond lengths. Pd2+ is bonded in a distorted L-shaped geometry to two equivalent Cl1- atoms. Both Pd–Cl bond lengths are 2.42 Å. H1+ is bonded in a linear geometry to two equivalent O2- atoms. Both H–O bond lengths are 1.20 Å. S4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of S–O bond distances ranging from 1.48–1.55 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent K1+ and one S4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one S4+ atom. In the third O2- site, O2- is bonded in a distorted water-like geometry to one K1+, one H1+, and one S4+ atom. Cl1- is bonded in a 5-coordinate geometry to four K1+ and one Pd2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3HPtS2(ClO3)2 by Materials Project

K3PtHS2(O3Cl)2 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to six O2- and two equivalent Cl1- atoms. There are a spread of K–O bond distances ranging from 2.80–3.04 Å. There are one shorter (3.38 Å) and one longer (3.40 Å) K–Cl bond lengths. In the second K1+ site, K1+ is bonded to two equivalent O2- and four equivalent Cl1- atoms to form distorted edge-sharing KCl4O2 pentagonal pyramids. Both K–O bond lengths are 2.76 Å. There are two shorter (3.18 Å) and two longer (3.20 Å) K–Cl bond lengths. Pt6+ is bonded in an L-shaped geometry to two equivalent Cl1- atoms. Both Pt–Cl bond lengths are 2.41 Å. H1+ is bonded in a linear geometry to two equivalent O2- atoms. Both H–O bond lengths are 1.20 Å. S2+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of S–O bond distances ranging from 1.48–1.54 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent K1+ and one S2+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one S2+ atom. In the third O2- site, O2- is bonded in a distorted water-like geometry to one K1+, one H1+, and one S2+ atom. Cl1- is bonded in a 5-coordinate geometry to four K1+ and one Pt6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KICl2 by Materials Project

KICl2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 5-coordinate geometry to five Cl atoms. There are a spread of K–Cl bond distances ranging from 3.16–3.63 Å. In the second K site, K is bonded in a 6-coordinate geometry to six Cl atoms. There are a spread of K–Cl bond distances ranging from 3.16–3.36 Å. There are two inequivalent I sites. In the first I site, I is bonded in a distorted linear geometry to two Cl atoms. There are one shorter (2.51 Å) and one longer (2.61 Å) I–Cl bond lengths. In the second I site, I is bonded in a linear geometry to two Cl atoms. There are one shorter (2.58 Å) and one longer (2.60 Å) I–Cl bond lengths. There are four inequivalent Cl sites. In the first Cl site, Cl is bonded in a distorted trigonal non-coplanar geometry to two equivalent K and one I atom. In the second Cl site, Cl is bonded to three K and one I atom to form a mixture of distorted edge and corner-sharing ClK3I tetrahedra. In the third Cl site, Cl is bonded to three K and one I atom to form a mixture of edge and corner-sharing ClK3I trigonal pyramids. In the fourth Cl site, Cl is bonded to three K and one I atom to form a mixture of edge and corner-sharing ClK3I tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K2PbO3 by Materials Project

K2PbO3 is beta Sn-derived structured and crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. There are two shorter (2.63 Å) and four longer (2.89 Å) K–O bond lengths. In the second K1+ site, K1+ is bonded to six equivalent O2- atoms to form KO6 octahedra that share edges with six equivalent PbO6 octahedra. All K–O bond lengths are 2.68 Å. Pb4+ is bonded to six equivalent O2- atoms to form PbO6 octahedra that share edges with three equivalent KO6 octahedra and edges with three equivalent PbO6 octahedra. All Pb–O bond lengths are 2.28 Å. O2- is bonded to four K1+ and two equivalent Pb4+ atoms to form a mixture of distorted corner, edge, and face-sharing OK4Pb2 octahedra. The corner-sharing octahedra tilt angles range from 0–49°.

36 MATERIALS SCIENCE↗