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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Y5Si3H by Materials Project

Y5Si3H crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Y sites. In the first Y site, Y is bonded in a 6-coordinate geometry to six equivalent Si atoms. All Y–Si bond lengths are 3.05 Å. In the second Y site, Y is bonded in a 7-coordinate geometry to five equivalent Si and two equivalent H atoms. There are a spread of Y–Si bond distances ranging from 2.90–3.35 Å. Both Y–H bond lengths are 2.63 Å. Si is bonded in a 9-coordinate geometry to nine Y atoms. H is bonded to six equivalent Y atoms to form face-sharing HY6 octahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y2Si3Rh by Materials Project

Y2RhSi3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Y sites. In the first Y site, Y is bonded to twelve equivalent Si atoms to form YSi12 cuboctahedra that share edges with twelve equivalent YSi8Rh4 cuboctahedra and faces with eight YSi12 cuboctahedra. There are six shorter (3.08 Å) and six longer (3.09 Å) Y–Si bond lengths. In the second Y site, Y is bonded to four equivalent Rh and eight equivalent Si atoms to form a mixture of edge and face-sharing YSi8Rh4 cuboctahedra. There are two shorter (3.06 Å) and two longer (3.12 Å) Y–Rh bond lengths. There are four shorter (3.08 Å) and four longer (3.11 Å) Y–Si bond lengths. Rh is bonded in a 3-coordinate geometry to six equivalent Y and three equivalent Si atoms. All Rh–Si bond lengths are 2.37 Å. Si is bonded in a 1-coordinate geometry to six Y, one Rh, and two equivalent Si atoms. Both Si–Si bond lengths are 2.36 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y2Si3Pd by Materials Project

Y2PdSi3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Y sites. In the first Y site, Y is bonded to four equivalent Pd and eight equivalent Si atoms to form a mixture of distorted edge and face-sharing YSi8Pd4 cuboctahedra. There are two shorter (3.03 Å) and two longer (3.20 Å) Y–Pd bond lengths. There are four shorter (3.05 Å) and four longer (3.15 Å) Y–Si bond lengths. In the second Y site, Y is bonded to twelve equivalent Si atoms to form a mixture of edge and face-sharing YSi12 cuboctahedra. There are six shorter (3.07 Å) and six longer (3.09 Å) Y–Si bond lengths. Pd is bonded in a 3-coordinate geometry to six equivalent Y and three equivalent Si atoms. All Pd–Si bond lengths are 2.41 Å. Si is bonded in a 1-coordinate geometry to six Y, one Pd, and two equivalent Si atoms. Both Si–Si bond lengths are 2.36 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y2Ga3(Fe7C)2 by Materials Project

Y2Ga3(Fe7C)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Y is bonded in a distorted bent 120 degrees geometry to six Fe, three Ga, and two equivalent C atoms. There are a spread of Y–Fe bond distances ranging from 3.10–3.36 Å. There are two shorter (3.36 Å) and one longer (3.43 Å) Y–Ga bond lengths. Both Y–C bond lengths are 2.54 Å. There are five inequivalent Fe sites. In the first Fe site, Fe is bonded in a 1-coordinate geometry to one Y, ten Fe, and three Ga atoms. There are a spread of Fe–Fe bond distances ranging from 2.36–2.79 Å. There are two shorter (2.69 Å) and one longer (2.70 Å) Fe–Ga bond lengths. In the second Fe site, Fe is bonded to three equivalent Y, seven Fe, and two equivalent Ga atoms to form FeY3Ga2Fe7 cuboctahedra that share corners with four equivalent FeY3Ga2Fe7 cuboctahedra, corners with five GaY2Fe10 cuboctahedra, corners with four equivalent CY2Fe4 octahedra, an edgeedge with one FeY3Ga2Fe7 cuboctahedra, edges with three GaY2Fe10 cuboctahedra, a faceface with one FeY3Ga2Fe7 cuboctahedra, faces with three GaY2Fe10 cuboctahedra, and faces with two equivalent CY2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 63–69°. There are a spread of Fe–Fe bond distances ranging from 2.55–2.66 Å. Both Fe–Ga bond lengths are 2.52 Å. In the third Fe site, Fe is bonded in a single-bond geometry to three Fe, two Ga, and one C atom. The Fe–Fe bond length is 2.62 Å. Both Fe–Ga bond lengths are 2.53 Å. The Fe–C bond length is 1.94 Å. In the fourth Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent Y, eight Fe, and two equivalent Ga atoms. Both Fe–Fe bond lengths are 2.54 Å. Both Fe–Ga bond lengths are 2.49 Å. In the fifth Fe site, Fe is bonded in a single-bond geometry to four Fe, two Ga, and one C atom. Both Fe–Ga bond lengths are 2.48 Å. The Fe–C bond length is 1.88 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded to two equivalent Y and ten Fe atoms to form distorted GaY2Fe10 cuboctahedra that share corners with four equivalent GaY2Fe10 cuboctahedra, corners with six equivalent FeY3Ga2Fe7 cuboctahedra, edges with two equivalent FeY3Ga2Fe7 cuboctahedra, faces with two equivalent FeY3Ga2Fe7 cuboctahedra, faces with four equivalent GaY2Fe10 cuboctahedra, and faces with four equivalent CY2Fe4 octahedra. In the second Ga site, Ga is bonded to two equivalent Y and ten Fe atoms to form distorted GaY2Fe10 cuboctahedra that share corners with two equivalent FeY3Ga2Fe7 cuboctahedra, corners with four GaY2Fe10 cuboctahedra, corners with two equivalent CY2Fe4 octahedra, edges with two equivalent FeY3Ga2Fe7 cuboctahedra, faces with two equivalent FeY3Ga2Fe7 cuboctahedra, faces with four GaY2Fe10 cuboctahedra, and faces with two equivalent CY2Fe4 octahedra. The corner-sharing octahedral tilt angles are 45°. C is bonded to two equivalent Y and four Fe atoms to form CY2Fe4 octahedra that share corners with two equivalent GaY2Fe10 cuboctahedra, corners with four equivalent FeY3Ga2Fe7 cuboctahedra, corners with two equivalent CY2Fe4 octahedra, faces with two equivalent FeY3Ga2Fe7 cuboctahedra, and faces with four GaY2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles are 62°.

36 MATERIALS SCIENCE↗
NASA NTRS2007

Comparison of Integrated Radiation Transport Models with TEPC Measurements for the Average Quality Factors in Spaceflights

The purpose of this work is to test our theoretical model for the interpretation of radiation data measured in space. During the space missions astronauts are exposed to the complex field of radiation type and kinetic energies from galactic cosmic rays (GCR), trapped protons, and sometimes solar particle events (SPEs). The tissue equivalent proportional counter (TEPC) is a simple time-dependent approach for radiation monitoring for astronauts on board the International Space Station. Another and a newer approach to Microdosimetry is the use of silicon-on-insulator (SOI) technology launched on the MidSTAR-1 mission in low Earth orbit (LEO). In the radiation protection practice, the average quality factor of a radiation field is defined as a function of linear energy transfer (LET), Q(sub ave)(LET). However, TEPC measures the average quality factor as a function of the lineal energy y, Q(sub ave)(y), defined as the average energy deposition in a volume divided by the average chord length of the volume. Lineal energy, y, deviates from LET due to energy straggling, delta-ray escape or entry, and nuclear fragments produced in the detector volume. Monte Carlo track structure simulation was employed to obtain the response of a TEPC irradiated with charged particle for an equivalent site diameter of 1 micron of wall-less counter. The calculated data of the energy absorption in the wall-less counter were compiled for various y values for several ion types at various discrete projectile energy levels. For the simulation of TEPC response from the mixed radiation environments inside a spacecraft, such as, Space Shuttle and International Space Station, the complete microdosimetric TEPC response, f( y, E, Z), were calculated with the Monte Carlo theoretical results by using the first order Lagrangian interpolation for a monovariate function at a given y value (y = 0.1 keV/micron 5000 keV/micron) at any projectile energy level (E = 0.01 MeV/u to 50,000 MeV/u) of each specific radiation type (Z = 1 to 28). Because the anomalous response has been observed at large event sizes in the experiment due to the escape of energy out of sensitive volume by delta-rays and the entry of delta-rays from the high-density wall into the low-density gas-volume cavity, Monte Carlo simulation was also made for the response of a walled-TEPC with wall thickness 2 mm and density 1 g/cm(exp 3). The radius of cavity was set to 6.35 mm and a gas density 7.874 x 10(exp -5) g/cm(exp 3). The response of the walled- and the wall-less counters were compared. The average quality factor Q(sub ave)(y) for trapped protons on STS-89 demonstrated the good agreement between the model calculations and flight TEPC data as shown. Using an integrated space radiation model (this includes the transport codes HZETRN and BRYNTRN, the quantum nuclear interaction model QMSFRG) and the resultant response distribution functions of walled-TEPC from Monte-Carlo track simulations, we compared model calculations with walled-TEPC measurements from NASA missions in LEO and made predictions for the lunar and the Mars missions. The Q(sub ave)(y) values for the trapped or the solar protons ranged from 1.9-2.5. This over-estimates the Qave(LET) values which ranged from 1.4-1.6. Both quantities increase with shield thickness due to nuclear fragmentation. The Q(sub ave)(LET) for the complete GCR spectra was found to be 3.5-4.5, while flight TEPCs measured 2.9-3.4 for Q(sub ave)(y). The GCR values are decreasing with the shield thickness. Our analysis for a proper interpretation of data supports the use of TEPCs for monitoring space radiation environment.

Kim, Myung-Hee Y.↗
DOE OSTI2024

Trap‐Engineering the Persistent Luminescence of Ca 3 Ga 4 O 9 :Tb 3+ via Al 3+ Substitution for Optical Data Storage

Abstract Optically stimulated luminescence (OSL) materials hold great potential for optical data storage (ODS) and anticounterfeiting applications. Nevertheless, the scarcity of suitable luminescent materials with deep‐level traps remains a significant obstacle. Herein, a host substation strategy have been employed to tune the persistent luminescence (PersL) and OSL properties of Ca 3 Ga 4 O 9 :Tb 3+ by Al 3+ substitution through trap engineering and demonstrated their potential. Specifically, the photoluminescence of the Ca 2.985 (Ga 1‐y% Al y% ) 4 O 9 :0.5%Tb 3+ of Tb 3+ is first investigated due to its different occupancies of Ca 2+ . The influence of host substitution on the crystal structure, trap depth, trap density, PersL, and OSL properties have further investigated. A series of strong PersL and OSL peaks from the Ca 2.985 (Ga 1‐y% Al y% ) 4 O 9 :0.5%Tb 3+ with bluish‐green emissions have been observed. The Ca 2.985 (Ga 1‐y% Al y% ) 4 O 9 :0.5%Tb 3+ have shown controllable photon release upon thermal and optical stimuli, enhancing their performance for ODS. Thermally stimulated luminescence suggests that vacancy and defect concentrations inside the Ca 3‐x% (Ga 1‐y% Al y% ) 4 O 9 :x%Tb 3+ can be manipulated by Tb 3+ doping and Al 3+ substitution, which ultimately leads to the formation of deep traps and a broad distribution of traps with increased deep trap concentration. The work demonstrates that trap engineering through Al 3 ⁺ substitution is an effective method for tuning PersL and OSL properties of Ca 2.985 (Ga 1‐y% Al y% ) 4 O 9 :0.5%Tb 3+ for ODS.

Abeywickrama, Thulitha M. [Department of Chemistry↗
DOE OSTI2022

Yttrium-based Double Perovskite Nanorods for Electrocatalysis

In this work, we investigate the effect of chemical composition of double perovskite nanorods on their versatile electrocatalytic activity not only as supports for the oxidation of small organic molecules but also as catalysts for the oxygen evolution reaction. Specifically, Y 2 CoMnO 6 and Y 2 NiMnO 6 nanorods with average diameters of 300 nm were prepared by a two-step hydrothermal method, in which the individual effects of synthetic parameters, such as the pH, annealing temperature, and precursor ratios on both the composition and morphology, were systematically investigated. When used as supports for Pt nanoparticles, Y 2 CoMnO 6 /Pt catalysts exhibited an electrocatalytic activity for the methanol oxidation reaction, which is 2.1 and 1.3 times higher than that measured for commercial Pt/C and Y 2 NiMnO 6 /Pt. Similarly, the Co-based catalyst support material displayed an ethanol oxidation activity, which is 2.3 times higher than both Pt/C and Y 2 NiMnO 6 /Pt. This clear enhancement in the activity for Y 2 CoMnO 6 can largely be attributed to strong metal-support interactions, as evidenced by a downshift in the binding energy of the Pt 4f bands, measured by XPS, which is often correlated not only with a downshift in the d-band center but also to a decreased adsorption of poisoning adsorbates. Moreover, when used as catalysts for the oxygen evolution reaction, Y 2 CoMnO 6 displayed a much greater activity as compared with Y 2 NiMnO 6 . This behavior can largely be attributed not only to a preponderance of comparatively more favorable oxidation states and electronic configurations but also to the formation of an active layer on the surface of the Y 2 CoMnO 6 catalyst, which collectively give rise to improved performance metrics and greater stability as compared with both IrO 2 and Y 2 NiMnO 6 . Overall, these results highlight the importance of both the chemical composition and the electronic structure of double perovskites, especially when utilized in multi-functional roles as either supports or catalysts.

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2021

Isolated Metal Sites in Cu–Zn–Y/Beta for Direct and Selective Butene-Rich C 3+ Olefin Formation from Ethanol

Direct and selective production of C 3+ olefins from bioethanol remains a critical challenge and important for the production of renewable transportation fuels such as aviation biofuels. In this study, we report a Cu–Zn–Y/Beta catalyst for selective ethanol conversion to butene-rich C 3+ olefins (88% selectivity at 100% ethanol conversion, 623 K), where the Cu, Zn, and Y sites are all highly dispersed. The ethanol-to-butene reaction network includes ethanol dehydrogenation, aldol condensation to crotonaldehyde, and hydrogenation to butyraldehyde, followed by further hydrogenation and dehydration reactions to form butenes. Cu sites play a critical role in promoting hydrogenation of the crotonaldehyde C═C bond to form butyraldehyde in the presence of hydrogen, making this a distinctive pathway from crotyl alcohol-based ethanol-to-butadiene reaction. Reaction rate measurements in the presence of ethanol and acetaldehyde (543 K, 12 kPa ethanol, 1.2 kPa acetaldehyde, 101.9 kPa H 2 ) over monometallic Zn/Beta and Y/Beta catalysts indicate that Y sites have higher C–C coupling rates than over Zn sites (initial C–C coupling rate, 6.1 × 10 –3 mol mol Y –1 s –1 vs 1.2 × 10 –3 mol mol Zn –1 s –1 ). Further, Lewis-acidic Y-site densities over Cu–Zn–Y/Beta with varied Y loadings are linearly correlated with the initial C–C coupling rates, suggesting that Lewis-acidic Y sites are the predominant sites that catalyze C–C coupling in Cu–Zn–Y/Beta catalysts. Control experiments show that the dealuminated Beta support is important to form higher density of Lewis-acidic Y sites in comparison with other supports such as silica, or deboronated MWW despite similar atomic dispersion of Y sites and Y–O coordination numbers over these supports, leading to more than 9 times higher C–C coupling rate per mole Y over dealuminated Beta relative to other supports. This study highlights the significance of unique combination of metal sites in contributing to the selective valorization of ethanol to C 3+ olefins, motivating for exploring multifunctional zeolite catalysts, where the presence of multiple sites with varying reactivities and functions allows for controlling the predominant molecular fluxes toward the desired products in complex reactions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

LLNL Kimberlina 1.2 NUFT Simulations June 2018 (v2)

This dataset contains the output 6,000, 3-dimensional reactive multi-phase flow and transport aquifer simulations of brine and CO2 leakage into a protective aquiver in California’s San Joaquin Valley and input data files detailing the geologic mesh, aquifer physical properties and CO2 and brine injection rates. This data set was generated as an ongoing effort with the US DOE National Risk Assessment Partnership (NRAP) to evaluate the effectiveness of monitoring techniques to detect brine and CO2 leakage from legacy wells into underground sources of drinking water overlaying a CO2 storage reservoir. Each simulation contains a unique set of input parameters, generated stochastically. The outputs consist of these upper three geologic layers (from top): the Etchegoin, Macoma-Chanac, Santa Margarita-McLure formations. These simulations span the several distances (1, 3 and 6 km or wells W31-0.2, W31-0.5 and W31-1.0, respectively) from the CO2 injector, initiated from bottom hole pressure and saturation to calculate wellbore leakage from the storage reservoir, with low and high regional groundwater gradients and wellbore leakage into 5 leaky nodes. The dataset includes 1,000 unique simulations for each distance, which each contain a unique aquifer heterogeneity, aquifer and caprock permeability, and two model generations are included with a high permeability (prod07) and hybrid permeability (prod09). The range of permeability distributions is listed in Table 1. Each model generation consists of 3,000 simulations. Included in the dataset are the leakage rates determined from 2D wellbore models which utilize the pressure and CO2 saturation from LBL's reservoir simulations, NUFT mesh files with distributed lithology, NUFT rocktab files which describe the material properties for the geologic layers and the NUFT input files and post-processed output 'ntab' files. Each ntab file contains spatial (rows) and temporal (columns) model output tables for each model cell, the locations (x,y,z) and dimensions for each cells (dx, dy, dz). Table 1. Permeability distribution ranges for prod07 and prod09 model generations Geologic Layer: Permeability Range (log10 m^2) prod07 prod09 Etchegoin -12.92 to -10.92 -13.70 to -11.44 Macoma-Chanac -12.72 to -10.72 -13.50 to -11.24 Santa Margarita-McLure -12.70 to -10.70 -13.48 to -11.22 The input files used to generate the model include which are included in the dataset are: Time series of CO2 leakage input into the model (ex: Q_brn.W31-0.2.sim1000.layers123.tab) Time series of CO2 leakage input into the model (ex: Q_CO2.W31-0.2.sim1000.layers123.tab) Physical properties of the aquifer materials detailing the aquifer porosity, solid density, partitioning coefficients, permeabilities and van-Genuchten parameters detailed in a NUFT rocktab file: (ex: sim1000.usnt.rocktab) Numerical mesh and geologic data assigned to each model cell detailed in a NUFT genmsh format (ex: sim1000.mesh_k16.prod07.trans.genmsh) The primary output parameters are: pH (use absolute value) Change in TDS (mg/kg) Change in Pressure (Pa) Change CO2 gas saturation (fraction range 0.0-1.0) for example, the directory /p/lscratchh/mansoor1/nrap/kimberlina/prod09/mainfiles/sim1000/W31- 0.2 contains: sim1000.W31-0.2.trans.pH.red.ntab sim1000.W31-0.2.no_bg.trans.TDS.red.ntab sim1000.W31-0.2.usnt.P.deltabg.red.ntab sim1000.W31-0.2.usnt.CO2_sat.deltabg.red.ntab Each row in the NTAB files consist of model output per numerical grid cell. Each output file contains 33 columns (variables), including the information of numerical records, geologic location and sizes and the simulated parameter values over time. The first 13 variables are about numerical records and relative geologic information for a simulation grid: 1. index: simulation index 2. i: the ith grid of x-axis 3. j: the ith grid of y-axis 4. k: the ith grid of z-axis 5. element_ref: element reference 6. nuft_ind: nuft index 7. x: grid location in the x axis direction 8. y: grid location in the y axis direction 9. z: grid location in the z axis direction 10. dx: grid length in the x axis direction 11. dy: grid length in the y axis direction 12. dz: grid length in the z axis direction 13. volume: volume of the simulation grid The remainder (14, 15, 16...) variables are the simulated parameter values over time, take Pressure as an example, are: 14. 0.0y: initial pressure per cell. 15. 10.0y: simulated pressure at the end of the 10th year. 16. 20.0y: simulated pressure at the end of the 20th year. ... (repeated for every 10 years until 200 years)... The model extends 10,000 m, 5,000 m and 1,411 m in the x,y and z dimensions, respectively. The mesh consists of 164,832 cells with mesh dimensions of 101 x 51 x 32 (nx, ny, nz), with cell dimensions ranging from 100 m laterally (along x and y-axis) and model layers are as designated in the z-axis: Layer 1: atmosphere (1e-30 m thick) Layer 2: upper caprock (10 m thick) Layers 3-13: Etchegoin (536.23 m thck) Layers 14-27: Macoma-Chanac (679.04 m thick) Layers 28-32: Santa Margarita-McLure (185.94 m thick) The wellbore is placed along node i=51, j=26, and extends vertically along 5 nodes from the top to the bottom of the model. Special instructions when extracting files: Each Gzip archive (ex: prod07.sim1000-sim00099.tar.gz) contains 100 simulations. Gzip archives should be transferred into base directories (ie. In Linux: mkdir prod07; mv prod07.*.tar.gz prod07/.) before extracting, or files will be overwritten. Each sub-simulation tree should have the following file structure pattern (using the linux 'tree' command): |-- prod07 | |-- sim0001 | |-- W31-0.2 | | |-- Q_brn.W31-0.2.sim0001.layers123.tab | | |-- Q_co2.W31-0.2.sim0001.layers123.tab | | |-- sim0001.W31-0.2.no_bg.trans.TDS.red.ntab | | |-- sim0001.W31-0.2.trans.pH.red.ntab | | |-- sim0001.W31-0.2.usnt.CO2_sat.deltabg.red.ntab | | |-- sim0001.W31-0.2.usnt.P.deltabg.red.ntab | |-- W31-0.5 | | |-- Q_brn.W31-0.5.sim0001.layers123.tab | | |-- Q_co2.W31-0.5.sim0001.layers123.tab | | |-- sim0001.W31-0.5.no_bg.trans.TDS.red.ntab | | |-- sim0001.W31-0.5.trans.pH.red.ntab | | |-- sim0001.W31-0.5.usnt.CO2_sat.deltabg.red.ntab | | |-- sim0001.W31-0.5.usnt.P.deltabg.red.ntab | |-- W31-1.0 | | |-- Q_brn.W31-1.0.sim0001.layers123.tab | | |-- Q_co2.W31-1.0.sim0001.layers123.tab | | |-- sim0001.W31-1.0.no_bg.trans.TDS.red.ntab | | |-- sim0001.W31-1.0.trans.pH.red.ntab | | |-- sim0001.W31-1.0.usnt.CO2_sat.deltabg.red.ntab | | |-- sim0001.W31-1.0.usnt.P.deltabg.red.ntab | |-- sim0001.mesh_k16.prod07.trans.genmsh Disclaimer This document was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor Lawrence Livermore National Security, LLC, nor any of their employees makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or Lawrence Livermore National Security, LLC. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or Lawrence Livermore National Security, LLC, and shall not be used for advertising or product endorsement purposes. Lawrence Livermore National Laboratory is operated by Lawrence Livermore National Security, LLC, for the U.S. Department of Energy, National Nuclear Security Administration under Contract DE-AC52-07NA27344. This report was reviewed and released as LLNL-MI-753464.

aquifer↗
DOE OSTI2022

Using Natural Gas Liquids to Recover Unconventional Oil and Gas Resources (Final Report)

This document presents final technical findings for the project Using Natural Gas Liquids to Recover Unconventional Oil and Gas Resources (FE0031782). The project is part of the U.S. Department of Energy Oil and Gas Program to develop and advance technologies that can significantly improve the recovery efficiencies of unconventional oil and gas resources. The overall objective of this project is to improve the ultimate recovery from unconventional oil and gas (UOG) resources in the United States by developing a method for using unrefined natural gas liquids (NGLs) as treatment fluids to improve hydrocarbon production. Horizontal extended-lateral drilling coupled with high volume hydraulic fracturing has significantly increased production from UOG resources in the U.S. However, the recovery efficiency is low compared to the estimated oil and gas in place. Recent data indicate that less than 10% of the oil in the liquid-rich UOG reservoirs is produced. Alternative completion methods using NGLs could increase production (Battelle, 2016; Wan et al., 2013; Wan, 2013; Downey et al, 2021); however, field validation tests are needed to develop an approach that is economical, efficient, and compatible in the UOG setting to advance towards commercial deployment. This project aims to develop and field test a method to improve recovery of oil resources in UOG shale plays by using Y-Grade NGLs, or a similar combination of NGLs, as treatment fluids. Refined NGLs have been used as a hydraulic treatment fluid in UOG plays for decades and are shown to be particularly effective because their miscibility with oil allows oil to flow more freely; however, the use of Y-Grade (unrefined) NGLs has not been studied. The use of Y-Grade NGLs would be advantageous over refined NGLs because Y-Grade NGLs do not require infrastructure or investment in refining and are already being produced from many UOG reservoirs. The concept was tested and monitored in the field at a commercial well site owned by project partner Hopco, Ltd. The project team, which consists of multiple oil and gas operators, Linde Gas North America LLC (Linde) and the Ohio Division of Geological Survey (ODGS), has extensive experience with oil and gas production in the Appalachian basin and the ability to work together quickly to solve technical issues and research needs. A key part of the proposed work was the use of existing wells for field testing and monitoring. A total of four wells (three vertical and one horizontal) were available for this project. One of the vertical wells was utilized as the test well for the NGL treatment test. A nearby vertical well was used for microseismic monitoring. The remaining vertical well and the horizontal well provided a baseline for typical UOG production in the oil window of the Utica/Point Pleasant (UPP). Major technical tasks of the project include characterization of the geotechnical properties of the UPP with an emphasis on the field site; design and planning for the NGLs testing; field testing and monitoring; analysis and integration of field data; and economic and resource/reserve assessment. The Shoman monitoring well and Doughty NGL treatment well were successfully plugged back during September-October 2020 in preparation for treatment and monitoring. A nitrogen diagnostic fracture injection test (DFIT) was completed on the Doughty well on July 22, 2021, consisting of 133,000 scf (91 Bbl.) of nitrogen. A nitrogen foam frac was completed in the Utica-Point Pleasant interval on August 17, 2021 with funding from outside sources. A microseismic monitoring array was installed in the Shoman well and monitored microseismic activity during the Doughty well frac job. Y-Grade NGL injection commenced on August 26, 2021. A total of 215 Bbl. was injected but the job was shut down due to a small leak on the suction hose on the pump truck. The Y-Grade treatment resumed on August 27, 2021 and an additional 726 Bbl. of Y-Grade NGL was injected at a well head pressure of 3850 psi. Total volume of injected Y-Grade over the two days of injection was 941 Bbl. The well was shut-in for 17 days following injection to allow the Y-Grade NGLs to soak on the formation. Y-Grade treatment flow back commenced on 9/13/2021 on a weekly basis. Production data, including surface pressures, oil, nitrogen, natural gas, and flow times was measured and recorded. Periodic gas samples were collected and analyzed to determine composition of flowback gas. As of July 2022, the treatment well had produced 726 Bbl of oil and 2,888 mcf gas. In August 2022, tubing and packer in the well were removed and a pump was installed to enhance oil recovery. Currently, the operator is producing the well about 2 days a week for a few hours. The performance of the NGL treatment test was evaluated based on reservoir simulations of the treatment process, processing of well testing data, analysis of micro seismic monitoring data, and production data analysis. This analysis suggested that oil production in the small test would continue through 2025. Upscaling the treatment to a horizontal Utica Point-Pleasant well would allow more oil recovery, but the process would involve more investment, services, and operational support. An economic analysis was conducted for scenarios aimed at upscaling the NGL treatment process for more typical horizontal UPP wells in the Appalachian Basin.

02 PETROLEUM↗
NASA NTRS2005

Methods of Improving a Digital Image Having White Zones

The present invention is a method of processing a digital image that is initially represented by digital data indexed to represent positions on a display. The digital data is indicative of an intensity value I,(x,y) for each position (x,y) in each i-th spectral band. The intensity value for each position in each i-th spectral band is adjusted to generate an adjusted intensity value for each position in each i-th spectral band in accordance with SIGMA (sup N)(sub n=1)W(sub n)(log I(sub i)(x,y)-log[I(sub i)(x,y)*F(sub n)(x,y)]), i = 1,...,S where W(sub n) is a weighting factor, "*" is the convolution operator and S is the total number of unique spectral bands. For each n, the function F(sub n)(x,y) is a unique surround function applied to each position (x,y) and N is the total number of unique surround functions. Each unique surround function is scaled to improve some aspect of the digital image, e.g., dynamic range compression, color constancy, and lightness rendition. The adjusted intensity value for each position in each i-th spectral band of the image is then filtered with a filter function to generate a filtered intensity value R(sub i)(x,y). To Prevent graying of white zones in the image, the maximum of the original intensity value I(sub i)(x,y) and filtered intensity value R(sub i)(x,y) is selected for display.

Glenn A Woodell↗
DOE OSTI2023

Measurement of Υ production in pp collisions at $\sqrt{s}$ = 5 TeV

The production cross-sections of Υ mesons, namely Υ(1S), Υ(2S) and Υ(3S), in pp collisions at $\sqrt{s}$ = 5 TeV are measured with a data sample corresponding to an integrated luminosity of 9.13 ± 0.18 pb –1 collected by the LHCb detector. The Υ mesons are reconstructed in the decay mode Υ → μ + μ – . Double differential cross-sections times branching fractions, as functions of the transverse momentum p T and the rapidity y of the Υ mesons, are measured in the range p T < 20 GeV/c and 2.0 < y < 4.5. The results integrated over these p T and y ranges are $\sigma \left(\textrm{Y}(1S)\right)\times \mathcal{B}\left(\textrm{Y}(1S)\to {\mu}^{+}{\mu}^{-}\right)=2101\pm 33\pm 83\ \textrm{pb},$ $\sigma \left(\textrm{Y}(2S)\right)\times \mathcal{B}\left(\textrm{Y}(2S)\to {\mu}^{+}{\mu}^{-}\right)=526\pm 20\pm 21\ \textrm{pb},$ $\sigma \left(\textrm{Y}(3S)\right)\times \mathcal{B}\left(\textrm{Y}(3S)\to {\mu}^{+}{\mu}^{-}\right)=242\pm 16\pm 10\ \textrm{pb},$ where the first uncertainties are statistical and the second are systematic. The ratios of cross-sections between measurements of two different Υ states and between measurements at different centre-of-mass energies are determined. The nuclear modification factor of Υ(1S) at $\sqrt{s}$ = 5 TeV is updated as well using the directly measured cross-section results from this analysis.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2020

Materials Data on Y2ReC2 by Materials Project

Y2ReC2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Y sites. In the first Y site, Y is bonded in a distorted rectangular see-saw-like geometry to four C atoms. There are a spread of Y–C bond distances ranging from 2.54–2.71 Å. In the second Y site, Y is bonded to five C atoms to form a mixture of corner and edge-sharing YC5 square pyramids. There are a spread of Y–C bond distances ranging from 2.51–2.58 Å. Re is bonded in a distorted trigonal planar geometry to three C atoms. There are a spread of Re–C bond distances ranging from 1.93–2.05 Å. There are two inequivalent C sites. In the first C site, C is bonded to five Y and one Re atom to form a mixture of corner and edge-sharing CY5Re octahedra. The corner-sharing octahedra tilt angles range from 3–39°. In the second C site, C is bonded to four Y and two equivalent Re atoms to form a mixture of corner and edge-sharing CY4Re2 octahedra. The corner-sharing octahedra tilt angles range from 11–39°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YAl3 by Materials Project

Al3Y crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Y sites. In the first Y site, Y is bonded to twelve Al atoms to form a mixture of corner and face-sharing YAl12 cuboctahedra. There are a spread of Y–Al bond distances ranging from 3.03–3.11 Å. In the second Y site, Y is bonded to twelve Al atoms to form a mixture of corner and face-sharing YAl12 cuboctahedra. There are six shorter (3.08 Å) and six longer (3.10 Å) Y–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a 10-coordinate geometry to four Y and six Al atoms. There are a spread of Al–Al bond distances ranging from 2.72–2.89 Å. In the second Al site, Al is bonded in a 12-coordinate geometry to four Y and eight Al atoms. All Al–Al bond lengths are 3.10 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y5Ga3 by Materials Project

Y5Ga3 crystallizes in the tetragonal P4/ncc space group. The structure is three-dimensional. there are two inequivalent Y sites. In the first Y site, Y is bonded to five Ga atoms to form a mixture of distorted face, edge, and corner-sharing YGa5 trigonal bipyramids. There are a spread of Y–Ga bond distances ranging from 3.07–3.21 Å. In the second Y site, Y is bonded in a 4-coordinate geometry to six Ga atoms. There are a spread of Y–Ga bond distances ranging from 3.04–3.65 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded in a 9-coordinate geometry to eight Y and one Ga atom. The Ga–Ga bond length is 2.66 Å. In the second Ga site, Ga is bonded in a 10-coordinate geometry to ten Y atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y15TmO24 by Materials Project

TmY15O24 is Spinel-like structured and crystallizes in the monoclinic C2 space group. The structure is three-dimensional. Tm3+ is bonded to six O2- atoms to form distorted TmO6 octahedra that share corners with six YO6 octahedra and edges with six YO6 octahedra. The corner-sharing octahedra tilt angles range from 53–55°. There are a spread of Tm–O bond distances ranging from 2.24–2.32 Å. There are nine inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded to six O2- atoms to form YO6 octahedra that share corners with six YO6 octahedra, an edgeedge with one TmO6 octahedra, and edges with five YO6 octahedra. The corner-sharing octahedra tilt angles range from 56–57°. There are three shorter (2.30 Å) and three longer (2.31 Å) Y–O bond lengths. In the second Y3+ site, Y3+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.35 Å. In the third Y3+ site, Y3+ is bonded to six O2- atoms to form distorted YO6 octahedra that share a cornercorner with one TmO6 octahedra, corners with five YO6 octahedra, and edges with six YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.35 Å. In the fourth Y3+ site, Y3+ is bonded to six O2- atoms to form distorted YO6 octahedra that share a cornercorner with one TmO6 octahedra, corners with five YO6 octahedra, and edges with six YO6 octahedra. The corner-sharing octahedra tilt angles range from 53–57°. There are a spread of Y–O bond distances ranging from 2.27–2.35 Å. In the fifth Y3+ site, Y3+ is bonded to six O2- atoms to form distorted YO6 octahedra that share corners with six YO6 octahedra, an edgeedge with one TmO6 octahedra, and edges with five YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.35 Å. In the sixth Y3+ site, Y3+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.35 Å. In the seventh Y3+ site, Y3+ is bonded to six O2- atoms to form YO6 octahedra that share a cornercorner with one TmO6 octahedra, corners with five YO6 octahedra, and edges with six YO6 octahedra. The corner-sharing octahedra tilt angles range from 55–56°. There are four shorter (2.30 Å) and two longer (2.31 Å) Y–O bond lengths. In the eighth Y3+ site, Y3+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.36 Å. In the ninth Y3+ site, Y3+ is bonded to six O2- atoms to form distorted YO6 octahedra that share corners with six YO6 octahedra, an edgeedge with one TmO6 octahedra, and edges with five YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.36 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the second O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the third O2- site, O2- is bonded to one Tm3+ and three Y3+ atoms to form a mixture of distorted edge and corner-sharing OY3Tm trigonal pyramids. In the fourth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the fifth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the sixth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the seventh O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the eighth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the ninth O2- site, O2- is bonded to one Tm3+ and three Y3+ atoms to form a mixture of distorted edge and corner-sharing OY3Tm trigonal pyramids. In the tenth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the eleventh O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the twelfth O2- site, O2- is bonded to one Tm3+ and three Y3+ atoms to form a mixture of distorted edge and corner-sharing OY3Tm trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SmY15O24 by Materials Project

SmY15O24 is Spinel-like structured and crystallizes in the monoclinic C2 space group. The structure is three-dimensional. Sm3+ is bonded to six O2- atoms to form distorted SmO6 octahedra that share corners with six YO6 octahedra and edges with six YO6 octahedra. The corner-sharing octahedra tilt angles range from 55–57°. There are a spread of Sm–O bond distances ranging from 2.31–2.40 Å. There are nine inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.36 Å. In the second Y3+ site, Y3+ is bonded to six O2- atoms to form YO6 octahedra that share corners with six YO6 octahedra, an edgeedge with one SmO6 octahedra, and edges with five YO6 octahedra. The corner-sharing octahedra tilt angles range from 55–56°. There are two shorter (2.30 Å) and four longer (2.31 Å) Y–O bond lengths. In the third Y3+ site, Y3+ is bonded to six O2- atoms to form distorted YO6 octahedra that share a cornercorner with one SmO6 octahedra, corners with five YO6 octahedra, and edges with six YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.36 Å. In the fourth Y3+ site, Y3+ is bonded to six O2- atoms to form distorted YO6 octahedra that share corners with six YO6 octahedra, an edgeedge with one SmO6 octahedra, and edges with five YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.36 Å. In the fifth Y3+ site, Y3+ is bonded to six O2- atoms to form distorted YO6 octahedra that share a cornercorner with one SmO6 octahedra, corners with five YO6 octahedra, and edges with six YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.36 Å. In the sixth Y3+ site, Y3+ is bonded to six O2- atoms to form YO6 octahedra that share a cornercorner with one SmO6 octahedra, corners with five YO6 octahedra, and edges with six YO6 octahedra. The corner-sharing octahedra tilt angles range from 55–57°. There are a spread of Y–O bond distances ranging from 2.29–2.31 Å. In the seventh Y3+ site, Y3+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.36 Å. In the eighth Y3+ site, Y3+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.35 Å. In the ninth Y3+ site, Y3+ is bonded to six O2- atoms to form distorted YO6 octahedra that share corners with six YO6 octahedra, an edgeedge with one SmO6 octahedra, and edges with five YO6 octahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–O bond distances ranging from 2.27–2.35 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded to four Y3+ atoms to form distorted OY4 trigonal pyramids that share corners with twelve OY4 trigonal pyramids and edges with four OSmY3 trigonal pyramids. In the second O2- site, O2- is bonded to four Y3+ atoms to form distorted OY4 trigonal pyramids that share corners with twelve OY4 trigonal pyramids and edges with four OSmY3 trigonal pyramids. In the third O2- site, O2- is bonded to one Sm3+ and three Y3+ atoms to form distorted OSmY3 trigonal pyramids that share corners with twelve OY4 trigonal pyramids and edges with four OSmY3 trigonal pyramids. In the fourth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the fifth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the sixth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the seventh O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the eighth O2- site, O2- is bonded to one Sm3+ and three Y3+ atoms to form a mixture of distorted edge and corner-sharing OSmY3 trigonal pyramids. In the ninth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the tenth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the eleventh O2- site, O2- is bonded to four Y3+ atoms to form a mixture of distorted edge and corner-sharing OY4 trigonal pyramids. In the twelfth O2- site, O2- is bonded to one Sm3+ and three Y3+ atoms to form a mixture of distorted edge and corner-sharing OSmY3 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y11Ta5O28 by Materials Project

Y11Ta5O28 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are nine inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Y–O bond distances ranging from 2.28–2.65 Å. In the second Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with two equivalent TaO6 octahedra, a cornercorner with one YO7 pentagonal bipyramid, edges with two equivalent TaO6 octahedra, and edges with three YO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 45°. There are a spread of Y–O bond distances ranging from 2.24–2.43 Å. In the third Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with two equivalent TaO6 octahedra, edges with two equivalent TaO6 octahedra, and edges with two equivalent YO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 61°. There are a spread of Y–O bond distances ranging from 2.22–2.48 Å. In the fourth Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with two equivalent TaO6 octahedra, a cornercorner with one YO7 pentagonal bipyramid, edges with two equivalent TaO6 octahedra, and an edgeedge with one YO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 47°. There are a spread of Y–O bond distances ranging from 2.24–2.45 Å. In the fifth Y3+ site, Y3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Y–O bond distances ranging from 2.23–2.69 Å. In the sixth Y3+ site, Y3+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.30–2.73 Å. In the seventh Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 hexagonal pyramids that share corners with two equivalent TaO6 octahedra, edges with two equivalent TaO6 octahedra, and edges with two equivalent TaO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 51°. There are a spread of Y–O bond distances ranging from 2.18–2.64 Å. In the eighth Y3+ site, Y3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Y–O bond distances ranging from 2.22–2.62 Å. In the ninth Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with two equivalent TaO6 octahedra, a cornercorner with one TaO7 pentagonal bipyramid, edges with two equivalent TaO6 octahedra, and an edgeedge with one TaO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 54°. There are a spread of Y–O bond distances ranging from 2.28–2.37 Å. There are three inequivalent Ta+4.60+ sites. In the first Ta+4.60+ site, Ta+4.60+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with two equivalent TaO6 octahedra, a cornercorner with one TaO7 pentagonal bipyramid, corners with three YO7 pentagonal bipyramids, an edgeedge with one YO7 hexagonal pyramid, and an edgeedge with one YO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 42–45°. There are a spread of Ta–O bond distances ranging from 1.96–2.06 Å. In the second Ta+4.60+ site, Ta+4.60+ is bonded to six O2- atoms to form distorted TaO6 octahedra that share a cornercorner with one YO7 hexagonal pyramid, corners with two equivalent TaO6 octahedra, a cornercorner with one YO7 pentagonal bipyramid, an edgeedge with one TaO7 pentagonal bipyramid, and edges with three YO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 32–69°. There are a spread of Ta–O bond distances ranging from 1.98–2.18 Å. In the third Ta+4.60+ site, Ta+4.60+ is bonded to seven O2- atoms to form TaO7 pentagonal bipyramids that share corners with two equivalent TaO6 octahedra, a cornercorner with one YO7 pentagonal bipyramid, edges with two equivalent YO7 hexagonal pyramids, edges with two equivalent TaO6 octahedra, and an edgeedge with one YO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 28°. There are a spread of Ta–O bond distances ranging from 1.99–2.13 Å. There are twenty inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ta+4.60+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ta+4.60+ atom. In the third O2- site, O2- is bonded to four Y3+ atoms to form OY4 tetrahedra that share corners with twelve OY3Ta tetrahedra, an edgeedge with one OY4 tetrahedra, and an edgeedge with one OY2Ta2 trigonal pyramid. In the fourth O2- site, O2- is bonded to four Y3+ atoms to form OY4 tetrahedra that share corners with twelve OY4 tetrahedra and an edgeedge with one OY3Ta tetrahedra. In the fifth O2- site, O2- is bonded to four Y3+ atoms to form OY4 tetrahedra that share corners with eight OY3Ta tetrahedra, corners with two equivalent OY2Ta2 trigonal pyramids, and edges with five OY3Ta tetrahedra. In the sixth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of edge and corner-sharing OY4 tetrahedra. In the seventh O2- site, O2- is bonded to three Y3+ and one Ta+4.60+ atom to form distorted OY3Ta tetrahedra that share corners with eleven OY3Ta tetrahedra, edges with two OY4 tetrahedra, and an edgeedge with one OY2Ta2 trigonal pyramid. In the eighth O2- site, O2- is bonded to three Y3+ and one Ta+4.60+ atom to form distorted OY3Ta tetrahedra that share corners with nine OY4 tetrahedra, edges with three OY3Ta tetrahedra, and an edgeedge with one OY2Ta2 trigonal pyramid. In the ninth O2- site, O2- is bonded to two Y3+ and two equivalent Ta+4.60+ atoms to form a mixture of distorted edge and corner-sharing OY2Ta2 trigonal pyramids. In the tenth O2- site, O2- is bonded to one Y3+ and three Ta+4.60+ atoms to form distorted OYTa3 tetrahedra that share corners with eight OY3Ta tetrahedra, corners with two equivalent OY2Ta2 trigonal pyramids, and edges with three OY3Ta tetrahedra. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to two Y3+ and two Ta+4.60+ atoms. In the twelfth O2- site, O2- is bonded to three Y3+ and one Ta+4.60+ atom to form distorted OY3Ta tetrahedra that share corners with ten OY3Ta tetrahedra, a cornercorner with one OY2Ta2 trigonal pyramid, and edges with five OY4 tetrahedra. In the thirteenth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of edge and corner-sharing OY4 tetrahedra. In the fourteenth O2- site, O2- is bonded to three Y3+ and one Ta+4.60+ atom to form distorted OY3Ta tetrahedra that share corners with fourteen OY4 tetrahedra and edges with three OY3Ta tetrahedra. In the fifteenth O2- site, O2- is bonded to four Y3+ atoms to form OY4 tetrahedra that share corners with eight OY3Ta tetrahedra and edges with three OY4 tetrahedra. In the sixteenth O2- site, O2- is bonded to three Y3+ and one Ta+4.60+ atom to form distorted OY3Ta tetrahedra that share corners with eight OY3Ta tetrahedra and edges with four OY4 tetrahedra. In the seventeenth O2- site, O2- is bonded to three Y3+ and one Ta+4.60+ atom to form a mixture of distorted edge and corner-sharing OY3Ta tetrahedra. In the eighteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Y3+ and two Ta+4.60+ atoms. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two equivalent Ta+4.60+ atoms. In the twentieth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two equivalent Ta+4.60+ atoms.

36 MATERIALS SCIENCE↗