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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Pr12Si5Se28 by Materials Project

Pr12Si5Se28 crystallizes in the trigonal P3 space group. The structure is three-dimensional. there are eight inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Pr–Se bond distances ranging from 2.89–3.26 Å. In the second Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Pr–Se bond distances ranging from 2.95–3.22 Å. In the third Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Pr–Se bond distances ranging from 2.95–3.25 Å. In the fourth Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Pr–Se bond distances ranging from 2.96–3.48 Å. In the fifth Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Pr–Se bond distances ranging from 2.90–3.47 Å. In the sixth Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Pr–Se bond distances ranging from 2.96–3.41 Å. In the seventh Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Pr–Se bond distances ranging from 2.91–3.55 Å. In the eighth Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Pr–Se bond distances ranging from 2.97–3.18 Å. There are ten inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded in an octahedral geometry to six Se2- atoms. There are three shorter (2.50 Å) and three longer (2.62 Å) Si–Se bond lengths. In the second Si4+ site, Si4+ is bonded in a tetrahedral geometry to four Se2- atoms. All Si–Se bond lengths are 2.29 Å. In the third Si4+ site, Si4+ is bonded in a tetrahedral geometry to four Se2- atoms. There are one shorter (2.28 Å) and three longer (2.31 Å) Si–Se bond lengths. In the fourth Si4+ site, Si4+ is bonded in a tetrahedral geometry to four Se2- atoms. There are one shorter (2.23 Å) and three longer (2.34 Å) Si–Se bond lengths. In the fifth Si4+ site, Si4+ is bonded in a tetrahedral geometry to four Se2- atoms. There are one shorter (2.24 Å) and three longer (2.31 Å) Si–Se bond lengths. In the sixth Si4+ site, Si4+ is bonded in an octahedral geometry to six Se2- atoms. There are three shorter (2.46 Å) and three longer (2.73 Å) Si–Se bond lengths. In the seventh Si4+ site, Si4+ is bonded in a tetrahedral geometry to four Se2- atoms. There are one shorter (2.25 Å) and three longer (2.31 Å) Si–Se bond lengths. In the eighth Si4+ site, Si4+ is bonded in a tetrahedral geometry to four Se2- atoms. There are three shorter (2.29 Å) and one longer (2.30 Å) Si–Se bond lengths. In the ninth Si4+ site, Si4+ is bonded in a tetrahedral geometry to four Se2- atoms. There are one shorter (2.23 Å) and three longer (2.32 Å) Si–Se bond lengths. In the tenth Si4+ site, Si4+ is bonded in a tetrahedral geometry to four Se2- atoms. There are one shorter (2.28 Å) and three longer (2.30 Å) Si–Se bond lengths. There are twenty-four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to four Pr3+ atoms. In the second Se2- site, Se2- is bonded to three Pr3+ and one Si4+ atom to form a mixture of distorted edge and corner-sharing SePr3Si trigonal pyramids. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to four Pr3+ and one Si4+ atom. In the fourth Se2- site, Se2- is bonded to four Pr3+ atoms to form distorted SePr4 trigonal pyramids that share corners with two SePr3Si tetrahedra and corners with two equivalent SePr4 trigonal pyramids. In the fifth Se2- site, Se2- is bonded in a 4-coordinate geometry to three Pr3+ and one Si4+ atom. In the sixth Se2- site, Se2- is bonded in a 4-coordinate geometry to three Pr3+ and one Si4+ atom. In the seventh Se2- site, Se2- is bonded in a 4-coordinate geometry to three Pr3+ and one Si4+ atom. In the eighth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Pr3+ and one Si4+ atom. In the ninth Se2- site, Se2- is bonded in a distorted tetrahedral geometry to three equivalent Pr3+ and one Si4+ atom. In the tenth Se2- site, Se2- is bonded to three equivalent Pr3+ and one Si4+ atom to form distorted corner-sharing SePr3Si tetrahedra. In the eleventh Se2- site, Se2- is bonded to three equivalent Pr3+ and one Si4+ atom to form distorted corner-sharing SePr3Si tetrahedra. In the twelfth Se2- site, Se2- is bonded to three equivalent Pr3+ and one Si4+ atom to form distorted corner-sharing SePr3Si tetrahedra. In the thirteenth Se2- site, Se2- is bonded in a 4-coordinate geometry to four Pr3+ atoms. In the fourteenth Se2- site, Se2- is bonded in a distorted square co-planar geometry to four Pr3+ atoms. In the fifteenth Se2- site, Se2- is bonded in a 5-coordinate geometry to four Pr3+ and one Si4+ atom. In the sixteenth Se2- site, Se2- is bonded in a 5-coordinate geometry to four Pr3+ and one Si4+ atom. In the seventeenth Se2- site, Se2- is bonded in a 4-coordinate geometry to three Pr3+ and one Si4+ atom. In the eighteenth Se2- site, Se2- is bonded in a 4-coordinate geometry to three Pr3+ and one Si4+ atom. In the nineteenth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Pr3+ and one Si4+ atom. In the twentieth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Pr3+ and one Si4+ atom. In the twenty-first Se2- site, Se2- is bonded to three equivalent Pr3+ and one Si4+ atom to form corner-sharing SePr3Si tetrahedra. In the twenty-second Se2- site, Se2- is bonded in a distorted tetrahedral geometry to three equivalent Pr3+ and one Si4+ atom. In the twenty-third Se2- site, Se2- is bonded in a distorted single-bond geometry to three equivalent Pr3+ and one Si4+ atom. In the twenty-fourth Se2- site, Se2- is bonded in a distorted tetrahedral geometry to three equivalent Pr3+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Optimization of edge bead removal (EBR) process to enhance defect reduction in optical lithography

Defect reduction remains a critical objective in the integrated circuit manufacturing process, particularly within the highly re-entrant lithography modules where minimizing defects is crucial. Defects at the wafer edge can contaminate lithography modules and downstream processing equipment, leading to redistribution onto the wafer surface and adversely affecting overall device yield. A persistent challenge in the resist coating process is the formation of resist edge beads, driven by the strong Van der Waals attraction of excess photoresist (PR) to itself and the underlying substrate. The edge bead removal (EBR) process is a standard cleaning step designed to eliminate these edge beads and prevent potential contamination. Here, in this study, we identify the sources of EBR induced defects and additional EBR process encroachment toward edge patterning during the EBR cleaning process. This study provides a comprehensive study aimed at optimizing the EBR cleaning process to effectively eliminate EBR-induced defects, thereby enhancing overall device yield. Specifically, we identify three primary defects induced by the EBR cleaning process: rainbow-type, finger-shaped, and teardrop-type defects. Our experimental study reveals that in addition to EBR rinse time, PR cast time is crucial parameters contributing to the formation of these defects. By properly optimizing the PR cast time and EBR rinse time, we were able to remove nearly 100 % of dense clusters of defects that were easily visible even at low magnification optical microscopy throughout the wafer edge. We observed that shorter PR casting times shows edge defects caused by inefficient EBR process because of insufficient time for PR to fully settle causing superfluous PR to continue flowing toward wafer edge during EBR clearing step, leading to partial removal of PR at the wafer edge and the formation of rainbow defects. Proper optimization of both PR casting time and EBR chemistries dispense time is essential to resolve these defects, ensuring efficient EBR cleaning process and improved overall device yield.

42 ENGINEERING↗
DOE OSTI2026

Coarse-Grained Simulations of Polyrotaxane Hydrogels under Quiescent and Shear Conditions

Cyclodextrin-based polyrotaxanes (PR) form hydrogels in water through cyclodextrin (CD) aggregation and crystallization. These networks can break under shear flows, making them versatile platforms for extrusion-based 3D printing. To optimize the material properties of 3D-printed PR gels, a microscopic understanding of the structural evolution during 3D printing is necessary. Here, we employ coarse-grained (CG) simulations to reveal the PR assembly process at the molecular level. Our simulations reproduce the experimental crystal morphologies of PR at varying concentrations and chain lengths under quiescent conditions. Using nonequilibrium simulations, we show shear flow ruptures crystalline domain connectivity in PR gels and stacks the lamellae in the gradient direction, allowing the materials to flow during 3D printing. After the cessation of flow, the anisotropic crystal alignment and absence of available dangling PR diminish the intercrystal connectivity. The printed materials are therefore mechanically weaker than the pristine hydrogels, in agreement with experimental results. Nonetheless, by relating the microscopic structural evolution with viscoelastic properties of PR gels and solutions, we elucidate how flow conditions and sample composition affect the 3D printing performance of PR hydrogels.

Smith, Cameron D. [Dartmouth College, Hanover, NH ↗
DOE OSTI2021

CO2 refixation is higher in leaves of woody species with high mesophyll and stomatal resistances to CO2 diffusion

Abstract The percentage of respiratory and photorespiratory CO2 refixed in leaves (Pr) represents part of the CO2 used in photosynthesis. The importance of Pr as well as differences between species and functional types are still not well investigated. In this study, we examine how Pr differs between six temperate and boreal woody species: Betula pendula, Quercus robur, Larix decidua, Pinus sylvestris, Picea abies and Vaccinium vitis-idaea. The study covers early and late successional species, deciduous broadleaves, deciduous conifers, evergreen conifers and evergreen broadleaves. We investigated whether some species or functional types had higher refixation percentages than others, whether leaf traits could predict higher Pr and whether these traits and their impact on Pr changed during growing seasons. Photosynthesis CO2 response (A/Ci)-curves, measured early, mid and late season, were used to estimate and compare Pr, mesophyll resistance (rm) and stomatal resistance (rs) to CO2 diffusion. Additionally, light images and transmission electron microscope images were used to approximate the fraction of intercellular airspace and cell wall thickness. We found that evergreens, especially late successional species, refixed a significantly higher amount of CO2 than the other species throughout the entire growing season. In addition, rm, rs and leaf mass per area, traits that typically are higher in evergreen species, were also significantly, positively correlated with Pr. We suggest that this is due to higher rm decreasing diffusion of (photo) respiratory CO2 out of the leaf. Cell wall thickness had a positive effect on Pr and rm, while the fraction of intercellular airspace had no effect. Both were significantly different between evergreen conifers and other types. Our findings suggest that species with a higher rm use a greater fraction of mitochondria-derived CO2, especially when stomatal conductance is low. This should be taken into account when modeling the overall CO2 fertilization effect for terrestrial ecosystems dominated by high rm species.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2022

GIF Supercritical Water Cooled Reactor: Proliferation Resistance and Physical Protection White Paper

This report is part of a series of six white papers, prepared jointly by the Proliferation Resistance and Physical Protection Working Group (PRPPWG) and the six System Steering Committees (SSCs) and provisional System Steering Committees (pSSCs). This publication is an update to a similar series published in 2011 presenting the status of Proliferation Resistance & Physical Protection (PR&PP) characteristics for each of the six systems selected by the Generation IV International Forum (GIF) for further research and development, namely: the Sodium-cooled fast Reactor (SFR), the Very high temperature reactor (VHTR), the gas-cooled fast reactor (GFR), the Molten salt reactor (MSR) and the Supercritical water–cooled reactor (SCWR). This white paper represents the status of Proliferation Resistance and Physical Protection (PR&PP) characteristics for the Supercritical Water-cooled Fast reactor (SCFR) reference designs selected by the Generation IV International Forum (GIF) SCWR System Steering Committee (SSC). The intent is to generate preliminary information about the PR&PP features of the SCWR reactor technology and to provide insights for optimizing their PR&PP performance for the benefit of SCWR system designers. It updates the SCWR analysis published in the 2011 report “Proliferation Resistance and Physical Protection of the Six Generation IV Nuclear Energy Systems”, prepared Jointly by the Proliferation Resistance and Physical Protection Working Group (PRPPWG) and the System Steering Committees and provisional System Steering Committees of the Generation IV International Forum, taking into account the evolution of both the systems, the GIF R&D activities, and an increased understanding of the PR&PP features. The white paper, prepared jointly by the GIF PRPPWG and the GIF SCWR SSC, follows the highlevel paradigm of the GIF PR&PP Evaluation Methodology to investigate the PR&PP features of the eight proposed GIF SCWR designs. Two small modular reactors, the Canadian SSR and the Canada/China/Europe ECC-SMART are also mentioned. An overview of the fuel cycles for the GIF designs are provided. For PR, the document analyses and discusses the proliferation resistance aspects in terms of robustness against State-based threats associated with diversion of materials, misuse of facilities, breakout scenarios, and production in clandestine facilities. Similarly, for PP, the document discusses the robustness against theft of material and sabotage by non-State actors. The document follows a common template adopted by all the white papers in the updated series.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2022

GIF Very High Temperature Reactor: Proliferation Resistance and Physical Protection White Paper

This report is part of a series of six white papers, prepared jointly by the Proliferation Resistance and Physical Protection Working Group (PRPPWG) and the six System Steering Committees (SSCs) and provisional System Steering Committees (pSSCs). This publication is an update to a similar series published in 2011 presenting the status of Proliferation Resistance & Physical Protection (PR&PP) characteristics for each of the six systems selected by the Generation IV International Forum (GIF) for further research and development, namely: the Sodium-cooled fast Reactor (SFR), the Very high temperature reactor (VHTR), the gas-cooled fast reactor (GFR), the Molten salt reactor (MSR) and the Supercritical water–cooled reactor (SCWR). This white paper represents the status of Proliferation Resistance and Physical Protection (PR&PP) characteristics for the Very-High-Temperature Reactor (VHTR) reference designs selected by the Generation IV International Forum (GIF) VHTR System Steering Committee (SSC). The intent is to generate preliminary information about the PR&PP features of the VHTR reactor technology and to provide insights for optimizing their PR&PP performance for the benefit of VHTR system designers. It updates the VHTR analysis published in the 2011 report “Proliferation Resistance and Physical Protection of the Six Generation IV Nuclear Energy Systems”, prepared Jointly by the Proliferation Resistance and Physical Protection Working Group (PRPPWG) and the System Steering Committees and provisional System Steering Committees of the Generation IV International Forum, taking into account the evolution of both the systems, the GIF R&D activities, and an increased understanding of the PR&PP features. The white paper, prepared jointly by the GIF PRPPWG and the GIF VHTR SSC, follows the high-level paradigm of the GIF PR&PP Evaluation Methodology to investigate the key points of PR&PP features extracted from the reference designs of VHTRs under consideration in various countries. A major update from the 2011 report is an explicit distinction between prismatic block-type VHTRs and pebble-bed VHTRs. The white paper also provides an overview of the TRISO fuel and fuel cycle. For PR, the document analyses and discusses the proliferation resistance aspects in terms of robustness against State-based threats associated with diversion of materials, misuse of facilities, breakout scenarios, and production in clandestine facilities. Similarly, for PP, the document discusses the robustness against theft of material and sabotage by non-State actors. The document follows a common template adopted by all the white papers in the updated series.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2020

Materials Data on PrNiGe3 by Materials Project

PrNiGe3 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Pr is bonded in a 4-coordinate geometry to four equivalent Ni and ten Ge atoms. All Pr–Ni bond lengths are 3.24 Å. There are a spread of Pr–Ge bond distances ranging from 3.14–3.29 Å. Ni is bonded in a 9-coordinate geometry to four equivalent Pr and five Ge atoms. There are a spread of Ni–Ge bond distances ranging from 2.36–2.39 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 2-coordinate geometry to two equivalent Pr, two equivalent Ni, and five Ge atoms. There are one shorter (2.49 Å) and four longer (2.96 Å) Ge–Ge bond lengths. In the second Ge site, Ge is bonded in a 2-coordinate geometry to two equivalent Pr, two equivalent Ni, and five Ge atoms. The Ge–Ge bond length is 2.49 Å. In the third Ge site, Ge is bonded in a 1-coordinate geometry to six equivalent Pr, one Ni, and two equivalent Ge atoms. Both Ge–Ge bond lengths are 2.57 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrCu6 by Materials Project

PrCu6 is Bergman Structure: Mg32(Al,Zn)49 Bergman-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Pr is bonded in a 6-coordinate geometry to nineteen Cu atoms. There are a spread of Pr–Cu bond distances ranging from 2.90–3.38 Å. There are five inequivalent Cu sites. In the first Cu site, Cu is bonded in a 2-coordinate geometry to four equivalent Pr and ten Cu atoms. There are a spread of Cu–Cu bond distances ranging from 2.53–3.10 Å. In the second Cu site, Cu is bonded to three equivalent Pr and nine Cu atoms to form a mixture of face, edge, and corner-sharing CuPr3Cu9 cuboctahedra. There are a spread of Cu–Cu bond distances ranging from 2.47–2.61 Å. In the third Cu site, Cu is bonded in a 3-coordinate geometry to three equivalent Pr and eight Cu atoms. There are two shorter (2.51 Å) and one longer (2.85 Å) Cu–Cu bond lengths. In the fourth Cu site, Cu is bonded in a 12-coordinate geometry to three equivalent Pr and nine Cu atoms. There are a spread of Cu–Cu bond distances ranging from 2.46–3.03 Å. In the fifth Cu site, Cu is bonded to three equivalent Pr and nine Cu atoms to form a mixture of face, edge, and corner-sharing CuPr3Cu9 cuboctahedra. There are one shorter (2.49 Å) and one longer (2.60 Å) Cu–Cu bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrMg12 by Materials Project

PrMg12 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded to ten Mg and two equivalent Pr atoms to form a mixture of distorted corner, edge, and face-sharing MgPr2Mg10 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 2.93–3.16 Å. Both Mg–Pr bond lengths are 3.94 Å. In the second Mg site, Mg is bonded in a distorted q6 geometry to ten Mg and two equivalent Pr atoms. There are a spread of Mg–Mg bond distances ranging from 3.12–3.35 Å. Both Mg–Pr bond lengths are 3.66 Å. In the third Mg site, Mg is bonded in a 10-coordinate geometry to nine Mg and one Pr atom. The Mg–Mg bond length is 3.06 Å. The Mg–Pr bond length is 3.65 Å. Pr is bonded in a 12-coordinate geometry to twenty Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr7BP2O17 by Materials Project

Pr7BP2O17 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are seven inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded to seven O2- atoms to form distorted PrO7 pentagonal bipyramids that share corners with three PO4 tetrahedra and an edgeedge with one PrO7 pentagonal bipyramid. There are a spread of Pr–O bond distances ranging from 2.31–2.59 Å. In the second Pr3+ site, Pr3+ is bonded to seven O2- atoms to form distorted PrO7 pentagonal bipyramids that share corners with two equivalent PO4 tetrahedra and an edgeedge with one PrO7 pentagonal bipyramid. There are a spread of Pr–O bond distances ranging from 2.35–2.62 Å. In the third Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.37–2.70 Å. In the fourth Pr3+ site, Pr3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Pr–O bond distances ranging from 2.37–2.63 Å. In the fifth Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.30–2.82 Å. In the sixth Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.28–2.89 Å. In the seventh Pr3+ site, Pr3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Pr–O bond distances ranging from 2.34–2.78 Å. B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.38–1.42 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent PrO7 pentagonal bipyramids. There is three shorter (1.55 Å) and one longer (1.57 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 three PrO7 pentagonal bipyramids. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. There are seventeen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three Pr3+ and one B3+ atom. In the second O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of distorted corner and edge-sharing OPr4 tetrahedra. In the third O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to three Pr3+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Pr3+ and one P5+ atom. In the sixth O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the seventh O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to three Pr3+ and one B3+ atom. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to three Pr3+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted single-bond geometry to two Pr3+ and one P5+ atom. In the eleventh O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the twelfth O2- site, O2- is bonded in a distorted single-bond geometry to three Pr3+ and one B3+ atom. In the thirteenth O2- site, O2- is bonded in a distorted single-bond geometry to two Pr3+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the fifteenth O2- site, O2- is bonded in a distorted single-bond geometry to two Pr3+ and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a distorted single-bond geometry to two Pr3+ and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a 1-coordinate geometry to three Pr3+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrAl22O34 by Materials Project

PrAl22O34 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. Pr is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Pr–O bond distances ranging from 2.54–3.24 Å. There are eighteen inequivalent Al sites. In the first Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with five AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.09 Å. In the second Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–59°. There is three shorter (1.82 Å) and one longer (1.83 Å) Al–O bond length. In the third Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with six AlO6 octahedra and a cornercorner with one AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–56°. There are a spread of Al–O bond distances ranging from 1.74–1.83 Å. In the fourth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with five AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.09 Å. In the fifth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with five AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.81–2.09 Å. In the sixth Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–59°. There are a spread of Al–O bond distances ranging from 1.81–1.85 Å. In the seventh Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–59°. There is three shorter (1.81 Å) and one longer (1.82 Å) Al–O bond length. In the eighth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with six AlO6 octahedra and a cornercorner with one AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–54°. There is one shorter (1.72 Å) and three longer (1.79 Å) Al–O bond length. In the ninth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with six AlO6 octahedra and a cornercorner with one AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–56°. There are a spread of Al–O bond distances ranging from 1.71–1.83 Å. In the tenth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with five AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.83–2.05 Å. In the eleventh Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with five AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.01 Å. In the twelfth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with five AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.83–2.04 Å. In the thirteenth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with six AlO4 tetrahedra and edges with six AlO6 octahedra. There is four shorter (1.90 Å) and two longer (1.91 Å) Al–O bond length. In the fourteenth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with five AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.01 Å. In the fifteenth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with five AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.81–2.08 Å. In the sixteenth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with six AlO6 octahedra and a cornercorner with one AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–54°. There are a spread of Al–O bond distances ranging from 1.75–1.79 Å. In the seventeenth Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–59°. There are a spread of Al–O bond distances ranging from 1.81–1.86 Å. In the eighteenth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with six AlO4 tetrahedra and edges with six AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.89–1.95 Å. There are twenty-six inequivalent O sites. In the first O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the second O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the third O site, O is bonded in a trigonal non-coplanar geometry to three Al atoms. In the fourth O site, O is bonded in a trigonal planar geometry to three Al atoms. In the fifth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the sixth O site, O is bonded in a trigonal planar geometry to three Al atoms. In the seventh O site, O is bonded in a trigonal planar geometry to three Al atoms. In the eighth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the ninth O site, O is bonded in a distorted bent 150 degrees geometry to two equivalent Pr and two Al atoms. In the tenth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the eleventh O site, O is bonded in a trigonal planar geometry to three Al atoms. In the twelfth O site, O is bonded in a trigonal non-coplanar geometry to three Al atoms. In the thirteenth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the fourteenth O site, O is bonded in a 4-coordinate geometry to one Pr and three Al atoms. In the fifteenth O site, O is bonded in a trigonal planar geometry to three Al atoms. In the sixteenth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the seventeenth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the eighteenth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the nineteenth O site, O is bonded to one Pr and three Al atoms to form distorted corner-sharing OPrAl3 tetrahedra. In the twentieth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the twenty-first O site, O is bonded in a trigonal non-coplanar geometry to three Al atoms. In the twenty-second O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the twenty-third O site, O is bonded to one Pr and three Al atoms to form distorted corner-sharing OPrAl3 tetrahedra. In the twenty-fourth O site, O is bonded in a trigonal planar geometry to three Al atoms. In the twenty-fifth O site, O is bonded in a 2-coordinate geometry to one Pr and two Al atoms. In the twenty-sixth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrTm3 by Materials Project

Tm3Pr is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are three inequivalent Tm sites. In the first Tm site, Tm is bonded to eight Tm and four equivalent Pr atoms to form TmPr4Tm8 cuboctahedra that share corners with four equivalent PrTm12 cuboctahedra, corners with fourteen TmPr4Tm8 cuboctahedra, edges with six equivalent PrTm12 cuboctahedra, edges with twelve TmPr4Tm8 cuboctahedra, faces with four equivalent PrTm12 cuboctahedra, and faces with sixteen TmPr4Tm8 cuboctahedra. There are a spread of Tm–Tm bond distances ranging from 3.50–3.66 Å. There are two shorter (3.53 Å) and two longer (3.61 Å) Tm–Pr bond lengths. In the second Tm site, Tm is bonded to eight Tm and four equivalent Pr atoms to form TmPr4Tm8 cuboctahedra that share corners with four equivalent PrTm12 cuboctahedra, corners with fourteen TmPr4Tm8 cuboctahedra, edges with six equivalent PrTm12 cuboctahedra, edges with twelve TmPr4Tm8 cuboctahedra, faces with four equivalent PrTm12 cuboctahedra, and faces with sixteen TmPr4Tm8 cuboctahedra. There are a spread of Tm–Tm bond distances ranging from 3.50–3.66 Å. There are two shorter (3.53 Å) and two longer (3.61 Å) Tm–Pr bond lengths. In the third Tm site, Tm is bonded to eight Tm and four equivalent Pr atoms to form TmPr4Tm8 cuboctahedra that share corners with four equivalent PrTm12 cuboctahedra, corners with fourteen TmPr4Tm8 cuboctahedra, edges with six equivalent PrTm12 cuboctahedra, edges with twelve TmPr4Tm8 cuboctahedra, faces with four equivalent PrTm12 cuboctahedra, and faces with sixteen TmPr4Tm8 cuboctahedra. There are one shorter (3.56 Å) and one longer (3.66 Å) Tm–Tm bond lengths. There are two shorter (3.53 Å) and two longer (3.61 Å) Tm–Pr bond lengths. Pr is bonded to twelve Tm atoms to form PrTm12 cuboctahedra that share corners with six equivalent PrTm12 cuboctahedra, corners with twelve TmPr4Tm8 cuboctahedra, edges with eighteen TmPr4Tm8 cuboctahedra, faces with eight equivalent PrTm12 cuboctahedra, and faces with twelve TmPr4Tm8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrAl4Co by Materials Project

PrCoAl4 crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. Pr is bonded in a 1-coordinate geometry to one Co and twelve Al atoms. The Pr–Co bond length is 2.99 Å. There are a spread of Pr–Al bond distances ranging from 3.11–3.28 Å. Co is bonded in a 9-coordinate geometry to one Pr and eight Al atoms. There are a spread of Co–Al bond distances ranging from 2.30–2.57 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded in a distorted linear geometry to two equivalent Pr, two equivalent Co, and eight Al atoms. There are four shorter (2.80 Å) and four longer (2.94 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a 4-coordinate geometry to two equivalent Pr, two equivalent Co, and eight Al atoms. There are two shorter (2.72 Å) and two longer (3.04 Å) Al–Al bond lengths. In the third Al site, Al is bonded in a 12-coordinate geometry to four equivalent Pr, two equivalent Co, and six Al atoms. There are one shorter (2.75 Å) and one longer (2.98 Å) Al–Al bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrLu3 by Materials Project

Lu3Pr is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are three inequivalent Lu sites. In the first Lu site, Lu is bonded to eight Lu and four equivalent Pr atoms to form LuPr4Lu8 cuboctahedra that share corners with four equivalent PrLu12 cuboctahedra, corners with fourteen equivalent LuPr4Lu8 cuboctahedra, edges with six equivalent PrLu12 cuboctahedra, edges with twelve LuPr4Lu8 cuboctahedra, faces with four equivalent PrLu12 cuboctahedra, and faces with sixteen LuPr4Lu8 cuboctahedra. There are a spread of Lu–Lu bond distances ranging from 3.47–3.64 Å. There are two shorter (3.51 Å) and two longer (3.58 Å) Lu–Pr bond lengths. In the second Lu site, Lu is bonded to eight Lu and four equivalent Pr atoms to form LuPr4Lu8 cuboctahedra that share corners with four equivalent PrLu12 cuboctahedra, corners with fourteen LuPr4Lu8 cuboctahedra, edges with six equivalent PrLu12 cuboctahedra, edges with twelve LuPr4Lu8 cuboctahedra, faces with four equivalent PrLu12 cuboctahedra, and faces with sixteen LuPr4Lu8 cuboctahedra. There are a spread of Lu–Lu bond distances ranging from 3.47–3.64 Å. There are two shorter (3.51 Å) and two longer (3.58 Å) Lu–Pr bond lengths. In the third Lu site, Lu is bonded to eight Lu and four equivalent Pr atoms to form LuPr4Lu8 cuboctahedra that share corners with four equivalent PrLu12 cuboctahedra, corners with fourteen LuPr4Lu8 cuboctahedra, edges with six equivalent PrLu12 cuboctahedra, edges with twelve LuPr4Lu8 cuboctahedra, faces with four equivalent PrLu12 cuboctahedra, and faces with sixteen LuPr4Lu8 cuboctahedra. There are two shorter (3.51 Å) and two longer (3.58 Å) Lu–Pr bond lengths. Pr is bonded to twelve Lu atoms to form PrLu12 cuboctahedra that share corners with six equivalent PrLu12 cuboctahedra, corners with twelve LuPr4Lu8 cuboctahedra, edges with eighteen LuPr4Lu8 cuboctahedra, faces with eight equivalent PrLu12 cuboctahedra, and faces with twelve LuPr4Lu8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2Al2Co15 by Materials Project

Pr2Co15Al2 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Pr is bonded in a 3-coordinate geometry to eighteen Co and one Al atom. There are a spread of Pr–Co bond distances ranging from 2.96–3.34 Å. The Pr–Al bond length is 3.06 Å. There are three inequivalent Co sites. In the first Co site, Co is bonded in a 12-coordinate geometry to two equivalent Pr, eight Co, and two equivalent Al atoms. There are four shorter (2.41 Å) and four longer (2.42 Å) Co–Co bond lengths. Both Co–Al bond lengths are 2.55 Å. In the second Co site, Co is bonded in a distorted q6 geometry to two equivalent Pr, eight Co, and two equivalent Al atoms. There are a spread of Co–Co bond distances ranging from 2.38–2.61 Å. Both Co–Al bond lengths are 2.71 Å. In the third Co site, Co is bonded to three equivalent Pr, eight Co, and one Al atom to form a mixture of distorted edge, corner, and face-sharing CoPr3AlCo8 cuboctahedra. Both Co–Co bond lengths are 2.49 Å. The Co–Al bond length is 2.58 Å. Al is bonded in a 6-coordinate geometry to one Pr, twelve Co, and one Al atom. The Al–Al bond length is 2.60 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaPr9Si6(SO12)2 by Materials Project

NaPr9Si6(SO12)2 crystallizes in the trigonal P3 space group. The structure is three-dimensional. Na1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Na–O bond distances ranging from 2.52–2.97 Å. There are five inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to two S2- and six O2- atoms. There are one shorter (2.98 Å) and one longer (3.02 Å) Pr–S bond lengths. There are a spread of Pr–O bond distances ranging from 2.39–2.94 Å. In the second Pr3+ site, Pr3+ is bonded in a 5-coordinate geometry to two S2- and five O2- atoms. There are one shorter (3.02 Å) and one longer (3.03 Å) Pr–S bond lengths. There are a spread of Pr–O bond distances ranging from 2.35–2.58 Å. In the third Pr3+ site, Pr3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Pr–O bond distances ranging from 2.43–2.75 Å. In the fourth Pr3+ site, Pr3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Pr–O bond distances ranging from 2.44–2.77 Å. In the fifth Pr3+ site, Pr3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Pr–O bond distances ranging from 2.45–2.81 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Si–O bond distances ranging from 1.61–1.67 Å. In the second Si4+ site, Si4+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.64 Å) and two longer (1.65 Å) Si–O bond length. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 12-coordinate geometry to six Pr3+ and six O2- atoms. There are three shorter (3.14 Å) and three longer (3.26 Å) S–O bond lengths. In the second S2- site, S2- is bonded in a distorted octahedral geometry to six Pr3+ atoms. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three Pr3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two Pr3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two Pr3+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three Pr3+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two Pr3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to three Pr3+, one Si4+, and one S2- atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to three Pr3+ and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two Pr3+, one Si4+, and one S2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2FeSi3 by Materials Project

Pr2FeSi3 is hexagonal omega structure-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Pr is bonded to three equivalent Fe and nine Si atoms to form a mixture of edge and face-sharing PrFe3Si9 cuboctahedra. All Pr–Fe bond lengths are 3.16 Å. There are three shorter (3.16 Å) and six longer (3.24 Å) Pr–Si bond lengths. Fe is bonded in a 3-coordinate geometry to six equivalent Pr and three equivalent Si atoms. All Fe–Si bond lengths are 2.34 Å. There are three inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent Si atoms. All Si–Si bond lengths are 2.34 Å. In the second Si site, Si is bonded in a 3-coordinate geometry to six equivalent Pr and three equivalent Fe atoms. In the third Si site, Si is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrAl4Ni by Materials Project

PrNiAl4 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Pr is bonded in a 9-coordinate geometry to two equivalent Ni and thirteen Al atoms. Both Pr–Ni bond lengths are 3.32 Å. There are a spread of Pr–Al bond distances ranging from 3.04–3.34 Å. Ni is bonded in a 7-coordinate geometry to two equivalent Pr and seven Al atoms. There are a spread of Ni–Al bond distances ranging from 2.31–2.51 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 10-coordinate geometry to four equivalent Pr and six Al atoms. There are four shorter (2.92 Å) and two longer (3.06 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a distorted single-bond geometry to three equivalent Pr, one Ni, and four equivalent Al atoms. In the third Al site, Al is bonded in a 3-coordinate geometry to three equivalent Pr, three equivalent Ni, and one Al atom.

36 MATERIALS SCIENCE↗