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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Sr5Cr3F19 by Materials Project

Sr5Cr3F19 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are ten inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Sr–F bond distances ranging from 2.40–2.68 Å. In the second Sr2+ site, Sr2+ is bonded to seven F1- atoms to form distorted SrF7 pentagonal bipyramids that share corners with two CrF6 octahedra, a cornercorner with one SrF7 pentagonal bipyramid, and edges with two CrF6 octahedra. The corner-sharing octahedra tilt angles range from 47–53°. There are a spread of Sr–F bond distances ranging from 2.41–2.64 Å. In the third Sr2+ site, Sr2+ is bonded to seven F1- atoms to form distorted SrF7 pentagonal bipyramids that share corners with three CrF6 octahedra, a cornercorner with one SrF7 pentagonal bipyramid, and an edgeedge with one CrF6 octahedra. The corner-sharing octahedra tilt angles range from 52–57°. There are a spread of Sr–F bond distances ranging from 2.47–2.72 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Sr–F bond distances ranging from 2.47–2.94 Å. In the fifth Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Sr–F bond distances ranging from 2.41–3.01 Å. In the sixth Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Sr–F bond distances ranging from 2.37–2.89 Å. In the seventh Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of Sr–F bond distances ranging from 2.43–2.65 Å. In the eighth Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Sr–F bond distances ranging from 2.38–3.02 Å. In the ninth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of Sr–F bond distances ranging from 2.34–2.68 Å. In the tenth Sr2+ site, Sr2+ is bonded in a 1-coordinate geometry to nine F1- atoms. There are a spread of Sr–F bond distances ranging from 2.39–3.11 Å. There are six inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six F1- atoms to form CrF6 octahedra that share a cornercorner with one CrF6 octahedra and a cornercorner with one SrF7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 1°. There are a spread of Cr–F bond distances ranging from 1.88–2.03 Å. In the second Cr3+ site, Cr3+ is bonded to six F1- atoms to form CrF6 octahedra that share edges with two SrF7 pentagonal bipyramids. There are a spread of Cr–F bond distances ranging from 1.92–2.01 Å. In the third Cr3+ site, Cr3+ is bonded to six F1- atoms to form CrF6 octahedra that share a cornercorner with one CrF6 octahedra, a cornercorner with one SrF7 pentagonal bipyramid, and an edgeedge with one SrF7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 38°. There are a spread of Cr–F bond distances ranging from 1.95–2.05 Å. In the fourth Cr3+ site, Cr3+ is bonded to six F1- atoms to form CrF6 octahedra that share a cornercorner with one CrF6 octahedra and a cornercorner with one SrF7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 1°. There are a spread of Cr–F bond distances ranging from 1.92–2.01 Å. In the fifth Cr3+ site, Cr3+ is bonded to six F1- atoms to form CrF6 octahedra that share a cornercorner with one CrF6 octahedra and a cornercorner with one SrF7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 38°. There are a spread of Cr–F bond distances ranging from 1.92–2.23 Å. In the sixth Cr3+ site, Cr3+ is bonded to six F1- atoms to form CrF6 octahedra that share a cornercorner with one SrF7 pentagonal bipyramid. There are a spread of Cr–F bond distances ranging from 1.91–1.98 Å. There are thirty-eight inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to two Sr2+ and one Cr3+ atom. In the second F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and one Cr3+ atom. In the third F1- site, F1- is bonded in a 2-coordinate geometry to two Sr2+ and one Cr3+ atom. In the fourth F1- site, F1- is bonded in a distorted trigonal planar geometry to three Sr2+ atoms. In the fifth F1- site, F1- is bonded in a 3-coordinate geometry to two Sr2+ and one Cr3+ atom. In the sixth F1- site, F1- is bonded in a 3-coordinate geometry to two Sr2+ and one Cr3+ atom. In the seventh F1- site, F1- is bonded in a 1-coordinate geometry to two Sr2+ and one Cr3+ atom. In the eighth F1- site, F1- is bonded in a distorted trigonal planar geometry to two Sr2+ and one Cr3+ atom. In the ninth F1- site, F1- is bonded in a 1-coordinate geometry to two Sr2+ and one Cr3+ atom. In the tenth F1- site, F1- is bonded in a distorted trigonal planar geometry to two Sr2+ and one Cr3+ atom. In the eleventh F1- site, F1- is bonded in a distorted trigonal planar geometry to two Sr2+ and one Cr3+ atom. In the twelfth F1- site, F1- is bonded in a 1-coordinate geometry to three Sr2+ and one Cr3+ atom. In the thirteenth F1- site, F1- is bonded in a 2-coordinate geometry to two Sr2+ and one Cr3+ atom. In the fourteenth F1- site, F1- is bonded in a 1-coordinate geometry to two Sr2+ and one Cr3+ atom. In the fifteenth F1- site, F1- is bonded in a 1-coordinate geometry to two Sr2+ and one Cr3+ atom. In the sixteenth F1- site, F1- is bonded in a 2-coordinate geometry to two Sr2+ and one Cr3+ atom. In the seventeenth F1- site, F1- is bonded in a 1-coordinate geometry to two Sr2+ and one Cr3+ atom. In the eighteenth F1- site, F1- is bonded in a 4-coordinate geometry to four Sr2+ atoms. In the nineteenth F1- site, F1- is bonded in a distorted trigonal planar geometry to three Sr2+ atoms. In the twentieth F1- site, F1- is bonded in a 1-coordinate geometry to two Sr2+ and one Cr3+ atom. In the twenty-first F1- site, F1- is bonded in a 3-coordinate geometry to two Sr2+ and one Cr3+ atom. In the twenty-second F1- site, F1- is bonded in a 3-coordinate geometry to two Sr2+ and one Cr3+ atom. In the twenty-third F1- site, F1- is bonded in a distorted single-bond geometry to two Sr2+ and one Cr3+ atom. In the twenty-fourth F1- site, F1- is bonded in a 1-coordinate geometry to three Sr2+ and one Cr3+ atom. In the twenty-fifth F1- site, F1- is bonded in a distorted trigonal non-coplanar geometry to two Sr2+ and one Cr3+ atom. In the twenty-sixth F1- site, F1- is bonded in a distorted bent 120 degrees geometry to two Sr2+ and one Cr3+ atom. In the twenty-seventh F1- site, F1- is bonded in a 3-coordinate geometry to two Sr2+ and one Cr3+ atom. In the twenty-eighth F1- site, F1- is bonded in a 3-coordinate geometry to one Sr2+ and two Cr3+ atoms. In the twenty-ninth F1- site, F1- is bonded in a distorted single-bond geometry to one Sr2+ and one Cr3+ atom. In the thirtieth F1- site, F1- is bonded in a distorted single-bond geometry to two Sr2+ and one Cr3+ atom. In the thirty-first F1- site, F1- is bonded in a distorted single-bond geometry to two Sr2+ and one Cr3+ atom. In the thirty-second F1- site, F1- is bonded in a 3-coordinate geometry to two Sr2+ and one Cr3+ atom. In the thirty-third F1- site, F1- is bonded in a 3-coordinate geometry to three Sr2+ atoms. In the thirty-fourth F1- site, F1- is bonded in a 2-coordinate geometry to two Sr2+ and one Cr3+ atom. In the thirty-fifth F1- site, F1- is bonded in a linear geometry to two Cr3+ atoms. In the thirty-sixth F1- site, F1- is bonded in a 1-coordinate geometry to two Sr2+ and one Cr3+ atom. In the thirty-seventh F1- site, F1- is bonded in a 3-coordinate geometry to two Sr2+ and one Cr3+ atom. In the thirty-eighth F1- site, F1- is bonded in a 3-coordinate geometry to two Sr2+ and one Cr3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr3Ca2P3O12F by Materials Project

Sr3Ca2P3O12F crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to six O2- and one F1- atom. There are a spread of Sr–O bond distances ranging from 2.50–2.82 Å. The Sr–F bond length is 2.51 Å. In the second Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to six O2- and one F1- atom. There are a spread of Sr–O bond distances ranging from 2.48–2.84 Å. The Sr–F bond length is 2.41 Å. In the third Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to six O2- and one F1- atom. There are a spread of Sr–O bond distances ranging from 2.48–2.85 Å. The Sr–F bond length is 2.41 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to six O2- and one F1- atom. There are a spread of Sr–O bond distances ranging from 2.49–2.86 Å. The Sr–F bond length is 2.41 Å. In the fifth Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.57–2.86 Å. In the sixth Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.56–2.82 Å. There are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.44–2.49 Å. In the second Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to nine O2- atoms. There are a spread of Ca–O bond distances ranging from 2.43–2.96 Å. In the third Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to six O2- and one F1- atom. There are a spread of Ca–O bond distances ranging from 2.36–2.89 Å. The Ca–F bond length is 2.36 Å. In the fourth Ca2+ site, Ca2+ is bonded to six O2- and one F1- atom to form distorted CaO6F pentagonal bipyramids that share corners with four PO4 tetrahedra and an edgeedge with one PO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.34–2.83 Å. The Ca–F bond length is 2.34 Å. There are six inequivalent P5+ sites. In the first P5+ site, P5+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.55 Å) and two longer (1.56 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent CaO6F pentagonal bipyramids. There is two shorter (1.55 Å) and two longer (1.56 Å) P–O bond length. In the third P5+ site, P5+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.55 Å) and two longer (1.56 Å) P–O bond length. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share an edgeedge with one CaO6F pentagonal bipyramid. There is two shorter (1.55 Å) and two longer (1.56 Å) P–O bond length. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one CaO6F pentagonal bipyramid. There is two shorter (1.55 Å) and two longer (1.56 Å) P–O bond length. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one CaO6F pentagonal bipyramid. There is two shorter (1.55 Å) and two longer (1.56 Å) P–O bond length. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, one Ca2+, and one P5+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, one Ca2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, two Ca2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, two Ca2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, two Ca2+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, two Ca2+, and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a 1-coordinate geometry to three Sr2+ and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a 1-coordinate geometry to three Sr2+ and one P5+ atom. In the eighteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. In the nineteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. In the twentieth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. In the twenty-first O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. In the twenty-second O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, two Ca2+, and one P5+ atom. In the twenty-third O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, two Ca2+, and one P5+ atom. In the twenty-fourth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, one Ca2+, and one P5+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a trigonal planar geometry to one Sr2+ and two Ca2+ atoms. In the second F1- site, F1- is bonded in a trigonal planar geometry to three Sr2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Super resolution for root imaging

Premise High‐resolution cameras are very helpful for plant phenotyping as their images enable tasks such as target vs. background discrimination and the measurement and analysis of fine above‐ground plant attributes. However, the acquisition of high‐resolution images of plant roots is more challenging than above‐ground data collection. An effective super‐resolution (SR) algorithm is therefore needed for overcoming the resolution limitations of sensors, reducing storage space requirements, and boosting the performance of subsequent analyses. Methods We propose an SR framework for enhancing images of plant roots using convolutional neural networks. We compare three alternatives for training the SR model: (i) training with non‐plant‐root images, (ii) training with plant‐root images, and (iii) pretraining the model with non‐plant‐root images and fine‐tuning with plant‐root images. The architectures of the SR models were based on two state‐of‐the‐art deep learning approaches: a fast SR convolutional neural network and an SR generative adversarial network. Results In our experiments, we observed that the SR models improved the quality of low‐resolution images of plant roots in an unseen data set in terms of the signal‐to‐noise ratio. We used a collection of publicly available data sets to demonstrate that the SR models outperform the basic bicubic interpolation, even when trained with non‐root data sets. Discussion The incorporation of a deep learning–based SR model in the imaging process enhances the quality of low‐resolution images of plant roots. We demonstrate that SR preprocessing boosts the performance of a machine learning system trained to separate plant roots from their background. Our segmentation experiments also show that high performance on this task can be achieved independently of the signal‐to‐noise ratio. We therefore conclude that the quality of the image enhancement depends on the desired application.

Ruiz‐Munoz, Jose F.↗
DOE OSTI2024

Scanning SQUID study of ferromagnetism and superconductivity in infinite-layer nickelates

Infinite-layer nickelates R 1-x Sr x NiO 2 (R = La, Pr, Nd) are a class of superconductors with structural similarities to cuprates. Although long-range antiferromagnetic order has not been observed for these materials, magnetic effects such as antiferromagnetic spin fluctuations and spin-glass behavior have been reported. Different experiments have drawn different conclusions about whether the pairing symmetry is s or d wave. In this paper, we applied a scanning superconducting quantum interference device (SQUID) to probe the magnetic behavior of film samples of three infinite-layer nickelates (La 0.85 Sr 0.15 NiO 2 , Pr 0.8 Sr 0.2 NiO 2 , and Nd 0.775 Sr 0.225 NiO 2 ) grown on SrTiO 3 (STO), each with a nominal thickness of 20 unit cells. In all three films, we observed a ferromagnetic background. We also measured the magnetic susceptibility above the superconducting critical temperature in Pr 0.8 Sr 0.2 NiO 2 and La 0.85 Sr 0.15 NiO 2 and identified a non-Curie-Weiss dynamic susceptibility. Both magnetic features are likely due to NiO x nanoparticles. We investigated superconductivity in Pr 0.8 Sr 0.2 NiO 2 and Nd 0.775 Sr 0.225 NiO 2 , which exhibited inhomogeneous diamagnetic screening. The superfluid density inferred from the diamagnetic susceptibility in relatively homogeneous regions shows T-linear behavior in both samples. Finally, we observed superconducting vortices in Nd 0.775 Sr 0.225 NiO 2 . We determined a Pearl length of 330 µm for Nd 0.775 Sr 0.225 NiO 2 at 300 mK, both from the strength of the diamagnetism and from the size and shape of the vortices. These results highlight the importance of considering NiO x particles when interpreting experimental results for these films.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2025

Deep Learning Super-Resolution X-Ray Computed Tomography Algorithms for Additive Manufacturing

Industrial X-ray computed tomography (XCT) is a nondestructive method for inspection and characterization of additively manufactured (AM) materials and parts. In practice, the resolution of XCT can be limited by factors such as detector binning, restricted field of view for large-scale objects, system blur, motion during scanning, and acquisition settings. These limitations can reduce the detectability of critical flaws such as pores, cracks, and lack of fusion. Super-resolution (SR) techniques offer a promising solution for improving the effective resolution and image quality of XCT reconstructions without the need for expensive hardware upgrades or laborious, time-consuming scans. In particular, deep learning-based SR methods have garnered attention in recent years as powerful tools for reconstructing high-resolution volumes from low-resolution inputs. In this work, a novel deep learning-based SR method is proposed for XCT scans of AM parts, and compared against several existing state-of-the-art (SOTA) methods. The proposed method, Simurgh-SR, is built on the pre-existing Simurgh framework and consists of a 2.5D U-Net trained to map low-quality inputs containing noise and artifacts to high-quality reconstructions characterized by higher flaw contrast, better noise texture, and reduced artifacts. The experimental results demonstrate superior performance of Simurgh-SR in performing 4× SR on real industrial XCT scans of thick 316L components, enhancing the structural similarity score and peak signal-to-noise ratio (>7dB) compared to the LR counterpart while improving the F1-score for flaw detection by more than 2.3× when compared to alternative SOTA SR methods. This improvement enables more accurate and significantly faster characterization of metal AM components. Additionally, Simurgh-SR was trained for both 2X and 4X SR and performs effectively at both levels, enabling the use of a single model for various SR factors.

Rahman, Obaid [ORNL] (ORCID:0000000277810840)↗
DOE OSTI2021

Measurement of Fission Product Concentration Profiles in AGR-3/4 TRISO Fuel Graphitic Matrix and Nuclear Graphites

The third Advanced Gas Reactor (AGR) irradiation experiment, AGR-3/4, was designed to investigate the migration of fission products in fuel compact graphitic matrix and reactor graphite components. Using destructive methods, radial fission product concentration profiles were measured for gamma-emitting fission products (e.g., Ag-110m, Cs-134, and Eu-154) and beta-emitting Sr-90 in irradiated graphitic and graphite components from six different AGR-3/4 irradiation capsules. These new measured concentration profiles can now be compared to non-destructive measurements and fission product transport simulations and will be used to derive new diffusivities and sorptivities to support refinement of fission product transport models and high-temperature gas-cooled reactor (HTGR) source-term analyses. Each capsule in the AGR-3/4 experiment had four fuel compacts in the middle of two concentric rings of graphitic matrix material, PCEA graphite, or IG-110 graphite. In addition to the approximately 1898 tristructural isotropic (TRISO) coated particles in each compact, there were 20 designed to fail (DTF) particles coated only in pyrocarbon so that they released fission products into the surrounding cylindrical rings of carbonaceous materials. Destructive sampling of the rings involved machining/milling material from around the circumference of the rings, collecting that material, and performing radiochemical analyses on it. Milling operations were performed in multiple steps or segments, and each segment was generally 0.508 mm (0.020 in) thick. Knowing the radial position at which each segment was milled, the volume of the milled material at each segment, and the fission product content in each segment, the radial fission product concentrations were constructed for select isotopes in each ring. Ag-110m profiles had the most variation. Some profiles were peaked at an inner or outer surface. Some were peaked at the middle of the ring wall thickness. Some increased radially outward, and some decreased radially outward. These types of variations and the fact that the measured profiles do not generally compare favorably with the transport model employed for AGR-3/4 may adversely impact the ability to extract reasonable transport parameters for this isotope. In many cases, the Cs-134 profiles decreased somewhat linearly in the outward radial direction, and in cursory comparisons, the shapes of these profiles appeared similar to those from model predictions. The step changes in concentration across the inner-outer ring gap were generally consistent with the model predictions as well. In some cases, there were local maxima in concentration at the outer surface of the rings. This suggests that fission products could have transported in the small gaps between the inner ring and the outer ring and between the outer ring and the sink ring such that some portion of a given fission product can bypass diffusion through the ring itself. The analysis of the small nubs on the outer surfaces of some of the outer rings revealed fission product concentrations in the nubs that were often higher than in the outermost segments of the rings. This further supports the hypothesis that short-circuit, gap transport occurred, causing relatively high surface concentrations on the outer surfaces of the rings. Eu-154 and Sr-90 profiles tend to have very similar shapes, suggesting that they transport via the same mechanisms. The observed profiles were indicative of a transport process where the isotopes are sorbed on the inner surface of the ring, but diffusion into the ring from that surface is quite slow. Some elevated concentrations of Sr-90 (relative to Eu-154) on the outer surface of a ring suggested that rapid, gas-gap transport of gaseous precursor Kr-90 and volatile Rb-90 could have occurred prior to their decaying to Sr-90. Overall, the Eu 154 and Sr-90 profiles were still very similar, which indicates that the transport of short-lived Sr-90 precursors is not a major effect. In some capsules, the qualitative Sr-90 behavior across the ring gaps was consistent with the model (using the available legacy Sr-90 transport parameters), but in other capsules the model was inconsistent with the measurements and seems to underestimate the amount of Sr-90 in the outer rings. The total ring Sr-90 inventories were estimated for all the rings that were subject to physical sampling. These results will be used to adjust the predicted particle and/or compact releases used in the AGR-3/4 fission product transport model. Given the different irradiation temperatures among the capsules and the rings, it was not possible to discern fundamental differences in the transport of isotopes within the different carbon materials, i.e., graphitic matrix, IG-110, or PCEA. It may be possible to do this in the course of determining transport from the concentration profiles in future work.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2020

Materials Data on Sr5Si3 by Materials Project

Sr5Si3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 4-coordinate geometry to four Si atoms. There are a spread of Sr–Si bond distances ranging from 3.24–3.47 Å. In the second Sr site, Sr is bonded to four equivalent Si atoms to form distorted edge-sharing SrSi4 tetrahedra. All Sr–Si bond lengths are 3.19 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded in a 6-coordinate geometry to six Sr atoms. In the second Si site, Si is bonded in a 8-coordinate geometry to eight equivalent Sr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr5Sn3 by Materials Project

Sr5Sn3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a square co-planar geometry to four equivalent Sn atoms. All Sr–Sn bond lengths are 3.43 Å. In the second Sr site, Sr is bonded to five Sn atoms to form a mixture of distorted edge, corner, and face-sharing SrSn5 trigonal bipyramids. There are a spread of Sr–Sn bond distances ranging from 3.40–3.65 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 8-coordinate geometry to eight equivalent Sr atoms. In the second Sn site, Sn is bonded in a 9-coordinate geometry to eight Sr and one Sn atom. The Sn–Sn bond length is 2.96 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr5Ge3 by Materials Project

Sr5Ge3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded to five Ge atoms to form a mixture of distorted face, edge, and corner-sharing SrGe5 trigonal bipyramids. There are a spread of Sr–Ge bond distances ranging from 3.29–3.48 Å. In the second Sr site, Sr is bonded in a square co-planar geometry to four equivalent Ge atoms. All Sr–Ge bond lengths are 3.29 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to eight Sr and one Ge atom. The Ge–Ge bond length is 2.63 Å. In the second Ge site, Ge is bonded in a 8-coordinate geometry to eight equivalent Sr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SrSn3 by Materials Project

SrSn3 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded to twelve Sn atoms to form a mixture of distorted corner and face-sharing SrSn12 cuboctahedra. There are a spread of Sr–Sn bond distances ranging from 3.50–3.63 Å. In the second Sr site, Sr is bonded to twelve Sn atoms to form a mixture of corner and face-sharing SrSn12 cuboctahedra. There are a spread of Sr–Sn bond distances ranging from 3.47–3.56 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 4-coordinate geometry to four Sr and two equivalent Sn atoms. Both Sn–Sn bond lengths are 3.28 Å. In the second Sn site, Sn is bonded in a 4-coordinate geometry to four Sr and four Sn atoms. Both Sn–Sn bond lengths are 3.06 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SrAg by Materials Project

SrAg crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 7-coordinate geometry to seven Ag atoms. There are a spread of Sr–Ag bond distances ranging from 3.36–3.49 Å. In the second Sr site, Sr is bonded in a 7-coordinate geometry to seven Ag atoms. There are a spread of Sr–Ag bond distances ranging from 3.36–3.47 Å. There are two inequivalent Ag sites. In the first Ag site, Ag is bonded in a 9-coordinate geometry to seven Sr and two equivalent Ag atoms. Both Ag–Ag bond lengths are 2.96 Å. In the second Ag site, Ag is bonded in a 9-coordinate geometry to seven Sr and two equivalent Ag atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr2Bi3 by Materials Project

Sr2Bi3 crystallizes in the orthorhombic Pnna space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 8-coordinate geometry to eight Bi atoms. There are a spread of Sr–Bi bond distances ranging from 3.49–3.82 Å. In the second Sr site, Sr is bonded in a 8-coordinate geometry to eight Bi atoms. There are a spread of Sr–Bi bond distances ranging from 3.44–3.62 Å. There are two inequivalent Bi sites. In the first Bi site, Bi is bonded in a 6-coordinate geometry to six Sr and two equivalent Bi atoms. Both Bi–Bi bond lengths are 3.35 Å. In the second Bi site, Bi is bonded in a 8-coordinate geometry to five Sr and three Bi atoms. There are one shorter (3.14 Å) and one longer (3.46 Å) Bi–Bi bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr4U2O9 by Materials Project

Sr4U2O9 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are nine inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with six UO6 octahedra. The corner-sharing octahedra tilt angles range from 32–43°. There are a spread of Sr–O bond distances ranging from 2.44–2.52 Å. In the second Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.48–3.18 Å. In the third Sr2+ site, Sr2+ is bonded in a 4-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.45–3.09 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.51–2.96 Å. In the fifth Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.54–3.25 Å. In the sixth Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with six UO6 octahedra. The corner-sharing octahedra tilt angles range from 33–41°. There are a spread of Sr–O bond distances ranging from 2.48–2.52 Å. In the seventh Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with six UO6 octahedra. The corner-sharing octahedra tilt angles range from 34–40°. There are a spread of Sr–O bond distances ranging from 2.46–2.50 Å. In the eighth Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.44–3.12 Å. In the ninth Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.47–3.17 Å. There are five inequivalent U5+ sites. In the first U5+ site, U5+ is bonded to six O2- atoms to form UO6 octahedra that share corners with three SrO6 octahedra and corners with three equivalent UO6 octahedra. The corner-sharing octahedra tilt angles range from 31–37°. There are a spread of U–O bond distances ranging from 2.06–2.33 Å. In the second U5+ site, U5+ is bonded to six O2- atoms to form corner-sharing UO6 octahedra. The corner-sharing octahedra tilt angles range from 31–37°. There are a spread of U–O bond distances ranging from 2.16–2.24 Å. In the third U5+ site, U5+ is bonded to six O2- atoms to form UO6 octahedra that share a cornercorner with one UO6 octahedra and corners with five SrO6 octahedra. The corner-sharing octahedra tilt angles range from 32–41°. There are a spread of U–O bond distances ranging from 2.09–2.38 Å. In the fourth U5+ site, U5+ is bonded to six O2- atoms to form UO6 octahedra that share corners with two equivalent UO6 octahedra and corners with four SrO6 octahedra. The corner-sharing octahedra tilt angles range from 33–43°. There are four shorter (2.11 Å) and two longer (2.33 Å) U–O bond lengths. In the fifth U5+ site, U5+ is bonded to six O2- atoms to form UO6 octahedra that share corners with two equivalent UO6 octahedra and corners with four SrO6 octahedra. The corner-sharing octahedra tilt angles range from 34–36°. There are a spread of U–O bond distances ranging from 2.09–2.36 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one U5+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two U5+ atoms. In the third O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one U5+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and two U5+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two U5+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one U5+ atom. In the seventh O2- site, O2- is bonded in a distorted see-saw-like geometry to three Sr2+ and one U5+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one U5+ atom. In the ninth O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one U5+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to four Sr2+ and one U5+ atom. In the eleventh O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one U5+ atom. In the twelfth O2- site, O2- is bonded to three Sr2+ and one U5+ atom to form distorted corner-sharing OSr3U tetrahedra. In the thirteenth O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one U5+ atom. In the fourteenth O2- site, O2- is bonded to two Sr2+ and two U5+ atoms to form distorted corner-sharing OSr2U2 tetrahedra. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to four Sr2+ and one U5+ atom. In the sixteenth O2- site, O2- is bonded in a 5-coordinate geometry to three Sr2+ and two U5+ atoms. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and two U5+ atoms. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one U5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr5Cd3 by Materials Project

Sr5Cd3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded to five Cd atoms to form a mixture of distorted edge, corner, and face-sharing SrCd5 trigonal bipyramids. There are a spread of Sr–Cd bond distances ranging from 3.56–3.66 Å. In the second Sr site, Sr is bonded in a square co-planar geometry to four equivalent Cd atoms. All Sr–Cd bond lengths are 3.44 Å. There are two inequivalent Cd sites. In the first Cd site, Cd is bonded in a 9-coordinate geometry to eight Sr and one Cd atom. The Cd–Cd bond length is 3.00 Å. In the second Cd site, Cd is bonded in a 8-coordinate geometry to eight equivalent Sr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr3Li3(NiN)4 by Materials Project

Li3Sr3(NiN)4 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Li sites. In the first Li site, Li is bonded in a linear geometry to two equivalent N atoms. Both Li–N bond lengths are 2.03 Å. In the second Li site, Li is bonded in a linear geometry to two equivalent N atoms. Both Li–N bond lengths are 2.03 Å. There are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 3-coordinate geometry to three N atoms. There are two shorter (2.65 Å) and one longer (2.71 Å) Sr–N bond lengths. In the second Sr site, Sr is bonded in a square co-planar geometry to four equivalent N atoms. All Sr–N bond lengths are 2.82 Å. Ni is bonded in a linear geometry to two N atoms. There is one shorter (1.76 Å) and one longer (1.77 Å) Ni–N bond length. There are two inequivalent N sites. In the first N site, N is bonded to four Sr and two equivalent Ni atoms to form a mixture of distorted edge and corner-sharing NSr4Ni2 octahedra. The corner-sharing octahedra tilt angles range from 0–50°. In the second N site, N is bonded to three Li, one Sr, and two equivalent Ni atoms to form distorted corner-sharing NSrLi3Ni2 octahedra. The corner-sharing octahedra tilt angles range from 0–50°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr5In3 by Materials Project

Sr5In3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded to five In atoms to form a mixture of distorted corner, edge, and face-sharing SrIn5 trigonal bipyramids. There are a spread of Sr–In bond distances ranging from 3.55–3.68 Å. In the second Sr site, Sr is bonded in a square co-planar geometry to four equivalent In atoms. All Sr–In bond lengths are 3.54 Å. There are two inequivalent In sites. In the first In site, In is bonded in a 9-coordinate geometry to eight Sr and one In atom. The In–In bond length is 2.90 Å. In the second In site, In is bonded in a 8-coordinate geometry to eight equivalent Sr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr9U9O34 by Materials Project

Sr9U9O34 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are nine inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.47–2.91 Å. In the second Sr2+ site, Sr2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.55–2.88 Å. In the third Sr2+ site, Sr2+ is bonded to seven O2- atoms to form distorted SrO7 hexagonal pyramids that share a cornercorner with one UO7 pentagonal bipyramid and edges with two UO7 pentagonal bipyramids. There are a spread of Sr–O bond distances ranging from 2.47–2.59 Å. In the fourth Sr2+ site, Sr2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.50–2.88 Å. In the fifth Sr2+ site, Sr2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.52–2.88 Å. In the sixth Sr2+ site, Sr2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.51–2.71 Å. In the seventh Sr2+ site, Sr2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.45–2.88 Å. In the eighth Sr2+ site, Sr2+ is bonded to seven O2- atoms to form distorted SrO7 hexagonal pyramids that share corners with three UO7 pentagonal bipyramids and an edgeedge with one UO7 pentagonal bipyramid. There are a spread of Sr–O bond distances ranging from 2.49–2.63 Å. In the ninth Sr2+ site, Sr2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.50–2.86 Å. There are nine inequivalent U+5.56+ sites. In the first U+5.56+ site, U+5.56+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of U–O bond distances ranging from 1.99–2.32 Å. In the second U+5.56+ site, U+5.56+ is bonded to seven O2- atoms to form distorted UO7 pentagonal bipyramids that share a cornercorner with one SrO7 hexagonal pyramid, corners with two UO7 pentagonal bipyramids, an edgeedge with one SrO7 hexagonal pyramid, and an edgeedge with one UO7 pentagonal bipyramid. There are a spread of U–O bond distances ranging from 2.00–2.38 Å. In the third U+5.56+ site, U+5.56+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of U–O bond distances ranging from 2.00–2.70 Å. In the fourth U+5.56+ site, U+5.56+ is bonded to seven O2- atoms to form distorted UO7 pentagonal bipyramids that share a cornercorner with one SrO7 hexagonal pyramid, an edgeedge with one SrO7 hexagonal pyramid, and an edgeedge with one UO7 pentagonal bipyramid. There are a spread of U–O bond distances ranging from 2.00–2.37 Å. In the fifth U+5.56+ site, U+5.56+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of U–O bond distances ranging from 1.99–2.44 Å. In the sixth U+5.56+ site, U+5.56+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of U–O bond distances ranging from 2.00–2.68 Å. In the seventh U+5.56+ site, U+5.56+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of U–O bond distances ranging from 1.98–2.40 Å. In the eighth U+5.56+ site, U+5.56+ is bonded to seven O2- atoms to form distorted UO7 pentagonal bipyramids that share a cornercorner with one SrO7 hexagonal pyramid and corners with two UO7 pentagonal bipyramids. There are a spread of U–O bond distances ranging from 2.00–2.33 Å. In the ninth U+5.56+ site, U+5.56+ is bonded to seven O2- atoms to form distorted UO7 pentagonal bipyramids that share a cornercorner with one SrO7 hexagonal pyramid, corners with two UO7 pentagonal bipyramids, and an edgeedge with one SrO7 hexagonal pyramid. There are a spread of U–O bond distances ranging from 2.01–2.34 Å. There are thirty-four inequivalent O2- sites. In the first O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+ and three U+5.56+ atoms. In the third O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+ and three U+5.56+ atoms. In the fifth O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and three U+5.56+ atoms. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+ and three U+5.56+ atoms. In the eighth O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the ninth O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form distorted OSr3U tetrahedra that share corners with eleven OSr3U tetrahedra and edges with four OSrU3 tetrahedra. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and two U+5.56+ atoms. In the eleventh O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the twelfth O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the thirteenth O2- site, O2- is bonded to one Sr2+ and three U+5.56+ atoms to form distorted OSrU3 tetrahedra that share corners with seven OSrU3 tetrahedra and edges with three OSr3U tetrahedra. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+ and three U+5.56+ atoms. In the fifteenth O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the sixteenth O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the seventeenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and two U+5.56+ atoms. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+ and three U+5.56+ atoms. In the nineteenth O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form distorted OSr3U tetrahedra that share corners with twelve OSr3U tetrahedra and edges with four OSrU3 tetrahedra. In the twentieth O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the twenty-first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and two U+5.56+ atoms. In the twenty-second O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+ and three U+5.56+ atoms. In the twenty-third O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the twenty-fourth O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the twenty-fifth O2- site, O2- is bonded to one Sr2+ and three U+5.56+ atoms to form a mixture of distorted edge and corner-sharing OSrU3 tetrahedra. In the twenty-sixth O2- site, O2- is bonded to one Sr2+ and three U+5.56+ atoms to form a mixture of distorted edge and corner-sharing OSrU3 tetrahedra. In the twenty-seventh O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form distorted OSr3U tetrahedra that share corners with eleven OSr3U tetrahedra and edges with four OSrU3 tetrahedra. In the twenty-eighth O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the twenty-ninth O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+ and three U+5.56+ atoms. In the thirtieth O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the thirty-first O2- site, O2- is bonded to one Sr2+ and three U+5.56+ atoms to form distorted OSrU3 tetrahedra that share corners with seven OSr3U tetrahedra and edges with four OSrU3 tetrahedra. In the thirty-second O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra. In the thirty-third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and two U+5.56+ atoms. In the thirty-fourth O2- site, O2- is bonded to three Sr2+ and one U+5.56+ atom to form a mixture of distorted edge and corner-sharing OSr3U tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr7Al12O25 by Materials Project

Sr7Al12O25 crystallizes in the trigonal P3 space group. The structure is three-dimensional. there are nine inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–3.00 Å. In the second Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–3.01 Å. In the third Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–2.74 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are one shorter (2.12 Å) and three longer (2.54 Å) Sr–O bond lengths. In the fifth Sr2+ site, Sr2+ is bonded to four O2- atoms to form distorted SrO4 trigonal pyramids that share corners with three equivalent AlO4 tetrahedra and corners with three equivalent AlO4 trigonal pyramids. There are one shorter (2.12 Å) and three longer (2.54 Å) Sr–O bond lengths. In the sixth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–2.75 Å. In the seventh Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–3.01 Å. In the eighth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–2.75 Å. In the ninth Sr2+ site, Sr2+ is bonded to four O2- atoms to form distorted SrO4 trigonal pyramids that share corners with three equivalent AlO4 tetrahedra and corners with three equivalent AlO4 trigonal pyramids. There are one shorter (2.12 Å) and three longer (2.53 Å) Sr–O bond lengths. There are twelve inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two AlO4 tetrahedra, a cornercorner with one SrO4 trigonal pyramid, and corners with two equivalent AlO4 trigonal pyramids. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. In the fourth Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 trigonal pyramids. There are a spread of Al–O bond distances ranging from 1.77–1.85 Å. In the fifth Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. In the sixth Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. In the seventh Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 trigonal pyramids that share corners with four AlO4 tetrahedra and a cornercorner with one SrO4 trigonal pyramid. There are a spread of Al–O bond distances ranging from 1.77–1.85 Å. In the eighth Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. In the ninth Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. In the tenth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 trigonal pyramids that share corners with four AlO4 tetrahedra and a cornercorner with one SrO4 trigonal pyramid. There are a spread of Al–O bond distances ranging from 1.77–1.85 Å. In the eleventh Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. In the twelfth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two AlO4 tetrahedra, a cornercorner with one SrO4 trigonal pyramid, and corners with two equivalent AlO4 trigonal pyramids. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. There are twenty-seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+ and two Al3+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+ and two Al3+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the fifth O2- site, O2- is bonded in a distorted tetrahedral geometry to two Sr2+ and two Al3+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+ and two Al3+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+ and two Al3+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the thirteenth O2- site, O2- is bonded in a single-bond geometry to one Sr2+ atom. In the fourteenth O2- site, O2- is bonded in a single-bond geometry to one Sr2+ atom. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the seventeenth O2- site, O2- is bonded in a distorted tetrahedral geometry to two Sr2+ and two Al3+ atoms. In the eighteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the twentieth O2- site, O2- is bonded in a distorted tetrahedral geometry to two Sr2+ and two Al3+ atoms. In the twenty-first O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+ and two Al3+ atoms. In the twenty-second O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the twenty-third O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the twenty-fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the twenty-fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+ and two Al3+ atoms. In the twenty-sixth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the twenty-seventh O2- site, O2- is bonded in a single-bond geometry to one Sr2+ atom.

36 MATERIALS SCIENCE↗