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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Pr(In2Au)2 by Materials Project

Pr(AuIn2)2 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. there are two inequivalent Pr sites. In the first Pr site, Pr is bonded in a 8-coordinate geometry to four Au and ten In atoms. There are a spread of Pr–Au bond distances ranging from 3.46–3.55 Å. There are a spread of Pr–In bond distances ranging from 3.34–3.76 Å. In the second Pr site, Pr is bonded in a 11-coordinate geometry to four Au and ten In atoms. There are a spread of Pr–Au bond distances ranging from 3.46–3.55 Å. There are a spread of Pr–In bond distances ranging from 3.34–3.76 Å. There are four inequivalent Au sites. In the first Au site, Au is bonded in a 9-coordinate geometry to two equivalent Pr and seven In atoms. There are a spread of Au–In bond distances ranging from 2.83–3.07 Å. In the second Au site, Au is bonded in a 7-coordinate geometry to two equivalent Pr and seven In atoms. There are a spread of Au–In bond distances ranging from 2.85–2.91 Å. In the third Au site, Au is bonded in a 9-coordinate geometry to two equivalent Pr and seven In atoms. There are a spread of Au–In bond distances ranging from 2.82–3.07 Å. In the fourth Au site, Au is bonded in a 7-coordinate geometry to two equivalent Pr and seven In atoms. There are a spread of Au–In bond distances ranging from 2.84–2.91 Å. There are eight inequivalent In sites. In the first In site, In is bonded in a 3-coordinate geometry to three Pr and three Au atoms. In the second In site, In is bonded in a 3-coordinate geometry to three Pr and three Au atoms. In the third In site, In is bonded to one Pr and four Au atoms to form a mixture of distorted edge and corner-sharing InPrAu4 tetrahedra. In the fourth In site, In is bonded in a 4-coordinate geometry to three Pr and four Au atoms. In the fifth In site, In is bonded in a 4-coordinate geometry to three Pr and four Au atoms. In the sixth In site, In is bonded in a 3-coordinate geometry to three Pr and three Au atoms. In the seventh In site, In is bonded to one Pr and four Au atoms to form a mixture of distorted edge and corner-sharing InPrAu4 tetrahedra. In the eighth In site, In is bonded in a 3-coordinate geometry to three Pr and three Au atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(MnSn)6 by Materials Project

Pr(MnSn)6 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Pr sites. In the first Pr site, Pr is bonded to eight Sn atoms to form distorted edge-sharing PrSn8 hexagonal bipyramids. There are a spread of Pr–Sn bond distances ranging from 3.08–3.23 Å. In the second Pr site, Pr is bonded to eight Sn atoms to form distorted edge-sharing PrSn8 hexagonal bipyramids. There are a spread of Pr–Sn bond distances ranging from 3.07–3.21 Å. There are four inequivalent Mn sites. In the first Mn site, Mn is bonded in a 12-coordinate geometry to six Sn atoms. There are four shorter (2.79 Å) and two longer (2.87 Å) Mn–Sn bond lengths. In the second Mn site, Mn is bonded in a 12-coordinate geometry to six Sn atoms. There are a spread of Mn–Sn bond distances ranging from 2.77–2.87 Å. In the third Mn site, Mn is bonded in a 12-coordinate geometry to six Sn atoms. There are a spread of Mn–Sn bond distances ranging from 2.74–2.87 Å. In the fourth Mn site, Mn is bonded in a 12-coordinate geometry to six Sn atoms. There are a spread of Mn–Sn bond distances ranging from 2.77–2.87 Å. There are nine inequivalent Sn sites. In the first Sn site, Sn is bonded in a 12-coordinate geometry to three Pr and six Mn atoms. In the second Sn site, Sn is bonded in a 6-coordinate geometry to six Mn atoms. In the third Sn site, Sn is bonded in a 12-coordinate geometry to three Pr and six Mn atoms. In the fourth Sn site, Sn is bonded in a 6-coordinate geometry to six Mn atoms. In the fifth Sn site, Sn is bonded in a 8-coordinate geometry to two equivalent Pr and six Mn atoms. In the sixth Sn site, Sn is bonded in a 7-coordinate geometry to one Pr and six Mn atoms. In the seventh Sn site, Sn is bonded in a 8-coordinate geometry to one Pr, six Mn, and one Sn atom. The Sn–Sn bond length is 3.02 Å. In the eighth Sn site, Sn is bonded in a 8-coordinate geometry to one Pr, six Mn, and one Sn atom. The Sn–Pr bond length is 3.07 Å. All Sn–Mn bond lengths are 2.87 Å. The Sn–Sn bond length is 3.02 Å. In the ninth Sn site, Sn is bonded in a 8-coordinate geometry to one Pr, six Mn, and one Sn atom. The Sn–Sn bond length is 3.01 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Quantum paramagnetism in a non-Kramers rare-earth oxide: Monoclinic Pr 2 Ti 2 O 7

Little is so far known about the magnetism of the A 2 B 2 O 7 monoclinic layered perovskites that replace the spin-ice supporting pyrochlore structure for r A /r B > 1.78. We show that high quality monoclinic Pr 2 Ti 2 O 7 single crystals with a three-dimensional network of non-Kramers Pr 3+ ions that interact through edge-sharing superexchange interactions, form a singlet ground-state quantum paramagnet that does not undergo any magnetic phase transitions down to, at least, 1.8 K. The chemical phase stability, structure, and magnetic properties of the layered perovskite Pr 2 Ti 2 O 7 were investigated using x-ray diffraction, transmission electron microscopy, and magnetization measurements. Synthesis of polycrystalline samples with the nominal compositions of Pr 2 Ti 2+x O 7 (–0.16 ≤ x ≤ 0.16 ) showed that deviations from the Pr 2 Ti 2 O 7 stoichiometry lead to secondary phases of related structures including the perovskite phase Pr 2/3 TiO 3 and the orthorhombic phases Pr 4 Ti 9 O 24 and Pr 2 TiO 5 . No indications of site disordering (stuffing and antistuffing) or vacancy defects were observed in the Pr 2 Ti 2 O 7 majority phase. A procedure for growth of high-structural-quality stoichiometric single crystals of Pr 2 Ti 2 O 7 by the traveling solvent floating zone method is reported. Thermomagnetic measurements of single-crystalline Pr 2 Ti 2 O 7 reveal an isolated singlet ground state that we associate with the low-symmetry crystal electric-field environments that split the (2J + 1 = 9)-fold degenerate spin-orbital multiplets of the four differently coordinated Pr 3+ ions into 36 isolated singlets resulting in an anisotropic temperature-independent van Vleck susceptibility at low T. Here, a small isotropic Curie term is associated with 0.96(2)% noninteracting Pr 4+ impurities.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr by Materials Project

Pr is alpha La structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Pr sites. In the first Pr site, Pr is bonded to twelve Pr atoms to form a mixture of edge, face, and corner-sharing PrPr12 cuboctahedra. There are six shorter (3.70 Å) and six longer (3.74 Å) Pr–Pr bond lengths. In the second Pr site, Pr is bonded to twelve Pr atoms to form a mixture of edge, face, and corner-sharing PrPr12 cuboctahedra. All Pr–Pr bond lengths are 3.74 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(Al5Os)2 by Materials Project

Pr(OsAl5)2 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Pr is bonded in a 10-coordinate geometry to four equivalent Os and sixteen Al atoms. All Pr–Os bond lengths are 3.49 Å. There are a spread of Pr–Al bond distances ranging from 3.18–3.70 Å. Os is bonded in a 10-coordinate geometry to two equivalent Pr and ten Al atoms. There are a spread of Os–Al bond distances ranging from 2.58–2.77 Å. There are five inequivalent Al sites. In the first Al site, Al is bonded in a 2-coordinate geometry to one Pr and two equivalent Os atoms. In the second Al site, Al is bonded in a distorted linear geometry to two equivalent Pr and two equivalent Os atoms. In the third Al site, Al is bonded in a 2-coordinate geometry to two equivalent Pr and two equivalent Os atoms. In the fourth Al site, Al is bonded in a distorted bent 120 degrees geometry to two equivalent Pr and two equivalent Os atoms. In the fifth Al site, Al is bonded in a 12-coordinate geometry to one Pr and two equivalent Os atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(Al5Ru)2 by Materials Project

Pr(RuAl5)2 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Pr is bonded in a 10-coordinate geometry to four equivalent Ru and sixteen Al atoms. All Pr–Ru bond lengths are 3.49 Å. There are a spread of Pr–Al bond distances ranging from 3.19–3.67 Å. Ru is bonded in a 10-coordinate geometry to two equivalent Pr and ten Al atoms. There are a spread of Ru–Al bond distances ranging from 2.58–2.77 Å. There are five inequivalent Al sites. In the first Al site, Al is bonded in a distorted bent 120 degrees geometry to two equivalent Pr and two equivalent Ru atoms. In the second Al site, Al is bonded in a 12-coordinate geometry to one Pr and two equivalent Ru atoms. In the third Al site, Al is bonded in a 2-coordinate geometry to two equivalent Pr and two equivalent Ru atoms. In the fourth Al site, Al is bonded in a 2-coordinate geometry to one Pr and two equivalent Ru atoms. In the fifth Al site, Al is bonded in a distorted linear geometry to two equivalent Pr and two equivalent Ru atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Experimental and modeling studies of PR and ND oxalate solubility to high ionic strengths: Insight into actinide(III) oxalates

Actinide oxalates are chemical compounds important to nuclear industry, ranging from actinide separation in waste reprocessing, to production of specialty actinides, and to disposal of high level nuclear waste (HLW) and spent nuclear fuel (SNF). In this study, the solubility constants for Pr 2 (C 2 O 4 ) 3 •10H 2 O and Nd 2 (C 2 O 4 ) 3 •10H 2 O by performing solubility experiments in HNO 3 and mixtures of HNO 3 and H 2 C 2 O 4 at 23.0 ± 0.2 °C have been determined. The targeted starting materials, Pr 2 (C 2 O 4 ) 3 •10H 2 O and Nd 2 (C 2 O 4 ) 3 •10H 2 O, were successfully synthesized at room temperature using PrCl 3 , NdCl 3 and oxalic acid as the source metrials. Then, we utilized the targeted solubility-controlling phases to conduct solubility measurements. There was no phase change over the entire periods of experiments, demonstrating that Pr 2 (C 2 O 4 ) 3 •10H 2 O and Nd 2 (C 2 O 4 ) 3 •10H 2 O were the solubility-controlling phases in our respective experiments. Based on our experimental data, we have developed a thermodynamic model for Pr 2 (C 2 O 4 ) 3 •10H 2 O and Nd 2 (C 2 O 4 ) 3 •10H 2 O in the mixtures of HNO 3 and H 2 C 2 O 4 to high ionic strengths. The model for Pr 2 (C 2 O 4 ) 3 •10H 2 O reproduces well the reported experimental data for Pu 2 (C 2 O 4 ) 3 •10H 2 O, which are not utilized for the model development, demonstrating that Pr(III) is an excellent analog for Pu(III). Similarly, the model for Nd 2 (C 2 O 4 ) 3 •10H 2 O reproduces the solubility of Am 2 (C 2 O 4 ) 3 •10H 2 O and Cm 2 (C 2 O 4 ) 3 •10H 2 O. The Pitzer model was used for the calculation of activity coefficients. Based on the published, well established model for dissociation constants for oxalic acid and stability constants for actinide-oxalate complexes [i.e., AmC 2 O 4 + , and Am(C 2 O 4 ) 2 - ] to high ionic strengths, we have obtained the solubility constants (log 10 K 0 ) for the following reactions at 25 °C, Pr 2 (C 2 O 4 ) 3 •10H 2 O ⇌ 2Pr 3+ + 3C 2 O 4 2- + 10H 2 O(l). Nd 2 (C 2 O 4 ) 3 •10H 2 O ⇌ 2Nd 3+ + 3C 2 O 4 2- + 10H 2 O(l). to be -30.82 ± 0.30 (2σ), and - 31.14 ± 0.35 (2σ), respectively. These values for can be directly applied to Pu 2 (C 2 O 4 ) 3 •10H 2 O, Am 2 (C 2 O 4 ) 3 •10H 2 O and Cm 2 (C 2 O 4 ) 3 •10H 2 O. The model established for actinide oxalates by this study provides the needed knowledge with regard to solubilities of actinide/REE oxalates at various ionic strengths, and is expected to find applications in many fields, including the geological disposal of nuclear waste and the mobility of REE under the surface conditions, as Pr 2 (C 2 O 4 ) 3 •10H 2 O and Nd 2 (C 2 O 4 ) 3 •10H 2 O can be regarded as the pure Pr and Nd end-members of deveroite, a recently discovered natural REE oxalate with the following stoichiometry, (Ce 1.01 Nd 0.33 La 0.32 Pr 0.11 Y 0.11 Sm 0.01 Pb 0.04 U 0.03 Th 0.01 Ca 0.04 ) 2.01 (C 2 O 4 ) 2.99 •9.99H 2 O. Regarding its importance in the geological disposal of nuclear waste, Am 2 (C 2 O 4 ) 3 •10H 2 O/Pu 2 (C 2 O 4 ) 3 •10H 2 O/Cm 2 (C 2 O 4 ) 3 •10H 2 O can be the source-term phase for actinides, as demonstrated by the instance in the disposal in clay/shale formations. This is exemplified by the stability of Am 2 (C 2 O 4 ) 3 •10H 2 O in comparison with Am(OH) 3 (am), Am(OH) 3 (s) and AmCO 3 (OH)(s) under the relevant geological repository conditions.

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

Materials Data on Pr(Ga4Co)2 by Materials Project

PrCo2Ga8 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to thirteen Ga atoms. There are a spread of Pr–Ga bond distances ranging from 3.13–3.39 Å. There are two inequivalent Co sites. In the first Co site, Co is bonded in a 9-coordinate geometry to nine Ga atoms. There are a spread of Co–Ga bond distances ranging from 2.36–2.67 Å. In the second Co site, Co is bonded in a 9-coordinate geometry to nine Ga atoms. There are a spread of Co–Ga bond distances ranging from 2.32–2.62 Å. There are nine inequivalent Ga sites. In the first Ga site, Ga is bonded in a 2-coordinate geometry to two equivalent Pr, two Co, and eight Ga atoms. There are a spread of Ga–Ga bond distances ranging from 2.83–2.92 Å. In the second Ga site, Ga is bonded in a 12-coordinate geometry to four equivalent Co and eight Ga atoms. There are a spread of Ga–Ga bond distances ranging from 2.64–2.95 Å. In the third Ga site, Ga is bonded in a 2-coordinate geometry to two equivalent Pr, two equivalent Co, and eight Ga atoms. There are four shorter (2.80 Å) and four longer (2.95 Å) Ga–Ga bond lengths. In the fourth Ga site, Ga is bonded in a 12-coordinate geometry to two equivalent Pr, two equivalent Co, and eight Ga atoms. There are a spread of Ga–Ga bond distances ranging from 2.65–3.12 Å. In the fifth Ga site, Ga is bonded in a 12-coordinate geometry to two equivalent Pr, two equivalent Co, and six Ga atoms. There are one shorter (2.69 Å) and one longer (2.82 Å) Ga–Ga bond lengths. In the sixth Ga site, Ga is bonded in a 12-coordinate geometry to two equivalent Pr, two equivalent Co, and eight Ga atoms. There are a spread of Ga–Ga bond distances ranging from 2.77–3.03 Å. In the seventh Ga site, Ga is bonded in a 12-coordinate geometry to two equivalent Pr, two equivalent Co, and eight Ga atoms. There are a spread of Ga–Ga bond distances ranging from 2.75–3.06 Å. In the eighth Ga site, Ga is bonded in a 12-coordinate geometry to two equivalent Pr, two equivalent Co, and eight Ga atoms. In the ninth Ga site, Ga is bonded in a 1-coordinate geometry to three Co and eight Ga atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(AlFe)6 by Materials Project

Pr(FeAl)6 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Pr is bonded in a 8-coordinate geometry to twelve Fe and eight Al atoms. There are four shorter (3.26 Å) and eight longer (3.32 Å) Pr–Fe bond lengths. There are a spread of Pr–Al bond distances ranging from 2.93–3.07 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded to two equivalent Pr, four Fe, and six Al atoms to form a mixture of distorted face, edge, and corner-sharing FePr2Al6Fe4 cuboctahedra. There are two shorter (2.51 Å) and two longer (2.52 Å) Fe–Fe bond lengths. There are a spread of Fe–Al bond distances ranging from 2.53–2.64 Å. In the second Fe site, Fe is bonded to two equivalent Pr, four equivalent Fe, and six Al atoms to form a mixture of distorted face, edge, and corner-sharing FePr2Al6Fe4 cuboctahedra. There are a spread of Fe–Al bond distances ranging from 2.60–2.73 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 10-coordinate geometry to one Pr, six Fe, and three Al atoms. There are one shorter (2.65 Å) and two longer (2.82 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a 7-coordinate geometry to one Pr, six Fe, and two equivalent Al atoms. Both Al–Al bond lengths are 2.96 Å. In the third Al site, Al is bonded in a 12-coordinate geometry to two equivalent Pr, six Fe, and four Al atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(PRh)2 by Materials Project

Pr(RhP)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to eight Rh and eight P atoms. There are four shorter (3.21 Å) and four longer (3.25 Å) Pr–Rh bond lengths. There are four shorter (3.14 Å) and four longer (3.18 Å) Pr–P bond lengths. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 12-coordinate geometry to four equivalent Pr and four equivalent P atoms. All Rh–P bond lengths are 2.48 Å. In the second Rh site, Rh is bonded in a 9-coordinate geometry to four equivalent Pr and five P atoms. There are four shorter (2.36 Å) and one longer (2.41 Å) Rh–P bond lengths. There are two inequivalent P sites. In the first P site, P is bonded in a 8-coordinate geometry to four equivalent Pr and four equivalent Rh atoms. In the second P site, P is bonded in a 9-coordinate geometry to four equivalent Pr and five Rh atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(InCu)6 by Materials Project

PrCu6In6 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Pr is bonded in a 8-coordinate geometry to twelve Cu and eight In atoms. There are four shorter (3.55 Å) and eight longer (3.57 Å) Pr–Cu bond lengths. There are a spread of Pr–In bond distances ranging from 3.13–3.30 Å. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded to two equivalent Pr, four Cu, and six In atoms to form a mixture of distorted edge, face, and corner-sharing CuPr2In6Cu4 cuboctahedra. There are two shorter (2.72 Å) and two longer (2.80 Å) Cu–Cu bond lengths. There are two shorter (2.76 Å) and four longer (2.84 Å) Cu–In bond lengths. In the second Cu site, Cu is bonded to two equivalent Pr, four equivalent Cu, and six In atoms to form a mixture of distorted edge, face, and corner-sharing CuPr2In6Cu4 cuboctahedra. There are a spread of Cu–In bond distances ranging from 2.80–2.95 Å. There are three inequivalent In sites. In the first In site, In is bonded in a 8-coordinate geometry to one Pr, six Cu, and one In atom. The In–In bond length is 2.97 Å. In the second In site, In is bonded in a 10-coordinate geometry to one Pr and six Cu atoms. In the third In site, In is bonded in a 12-coordinate geometry to two equivalent Pr and six Cu atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(GePt)2 by Materials Project

Pr(PtGe)2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to eight Pt and eight Ge atoms. There are a spread of Pr–Pt bond distances ranging from 3.30–3.44 Å. There are a spread of Pr–Ge bond distances ranging from 3.27–3.42 Å. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded in a 9-coordinate geometry to four equivalent Pr and five Ge atoms. There are one shorter (2.48 Å) and four longer (2.53 Å) Pt–Ge bond lengths. In the second Pt site, Pt is bonded in a 4-coordinate geometry to four equivalent Pr and four equivalent Ge atoms. There are a spread of Pt–Ge bond distances ranging from 2.56–2.58 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent Pr and five Pt atoms. In the second Ge site, Ge is bonded in a 4-coordinate geometry to four equivalent Pr and four equivalent Pt atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Improving the performance for direct electrolysis of CO 2 in solid oxide electrolysis cells with a Sr 1.9 Fe 1.5 Mo 0.5 O 6– δ electrode via infiltration of Pr 6 O 11 nanoparticles

Direct CO 2 electrolysis using solid oxide electrolysis cells (CO 2 -SOECs) holds promise to efficiently convert carbon dioxide to carbon monoxide and oxygen. Cathodes with desirable catalytic activity and chemical stability play a critical role in the development of direct CO 2 -SOECs. Although Sr 2 Fe 1.5 Mo 0.5 O 6–δ (SFM) has exhibited promise for direct CO 2 -SOECs due to its redox stability, it suffers from insufficient activity for the CO 2 reduction reaction (CO 2 RR). Here we report interface engineering of nanosized Pr 6 O 11 on the SFM cathode obtained through infiltration to promote the CO 2 RR performance for direct CO 2 -SOECs. The effect of Pr 6 O 11 loading on the performance of the CO 2 RR is systematically investigated. At 800 °C, the current density of the Pr 6 O 11 infiltrated SFM cathode with an optimum Pr 6 O 11 loading of 14.8 wt% reaches 1.61 A cm –2 at 1.5 V, more than double that of the SFM cathode (0.76 A cm –2 ) under the same operating conditions. X-ray photoelectron spectroscopy (XPS) characterization and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis indicate that the adsorption ability of CO 2 on the SFM cathode has been significantly improved by the formation of Pr 6 O 11 . Temperature-programmed desorption (TPD) of CO 2 measurements further manifest that a 14.8 wt% Pr 6 O 11 -SFM cathode has better CO desorption capacity. In addition, polarization resistance of the SFM cathode has significantly decreased with the addition of Pr 6 O 11 . Three-electrode measurement was used to analyze the improved electrode kinetics. Finally, these results demonstrate that the formation of Pr 6 O 11 in the SFM cathode through infiltration is a promising approach for increasing CO 2 RR activity for CO 2 -SOECs.

03 NATURAL GAS↗
DOE OSTI2020

Materials Data on Pr(Al2Cu)4 by Materials Project

Pr(CuAl2)4 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to eight equivalent Cu and twelve Al atoms. All Pr–Cu bond lengths are 3.41 Å. There are four shorter (3.11 Å) and eight longer (3.27 Å) Pr–Al bond lengths. Cu is bonded to two equivalent Pr, two equivalent Cu, and eight Al atoms to form a mixture of distorted face, edge, and corner-sharing CuPr2Al8Cu2 cuboctahedra. Both Cu–Cu bond lengths are 2.60 Å. There are four shorter (2.59 Å) and four longer (2.73 Å) Cu–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a 12-coordinate geometry to two equivalent Pr, four equivalent Cu, and six Al atoms. There are a spread of Al–Al bond distances ranging from 2.80–2.84 Å. In the second Al site, Al is bonded in a 10-coordinate geometry to one Pr, four equivalent Cu, and five Al atoms. The Al–Al bond length is 2.69 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(FeO3)2 by Materials Project

Pr(FeO3)2 crystallizes in the orthorhombic Pmn2_1 space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to twelve O atoms. There are a spread of Pr–O bond distances ranging from 2.47–3.07 Å. Fe is bonded to six O atoms to form corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 11–17°. There are a spread of Fe–O bond distances ranging from 1.91–1.95 Å. There are four inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to two equivalent Pr and two equivalent Fe atoms. In the second O site, O is bonded in a 3-coordinate geometry to two equivalent Pr and two equivalent Fe atoms. In the third O site, O is bonded in a distorted rectangular see-saw-like geometry to two equivalent Pr and two equivalent Fe atoms. In the fourth O site, O is bonded in a 4-coordinate geometry to two equivalent Pr and two equivalent Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(Re2Si)2 by Materials Project

Pr(Re2Si)2 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to eight Re and eight equivalent Si atoms. There are four shorter (3.37 Å) and four longer (3.47 Å) Pr–Re bond lengths. All Pr–Si bond lengths are 3.20 Å. There are two inequivalent Re sites. In the first Re site, Re is bonded in a 12-coordinate geometry to two equivalent Pr, eight Re, and two equivalent Si atoms. There are a spread of Re–Re bond distances ranging from 2.62–2.94 Å. Both Re–Si bond lengths are 2.52 Å. In the second Re site, Re is bonded to two equivalent Pr, eight Re, and two equivalent Si atoms to form a mixture of distorted edge, face, and corner-sharing RePr2Re8Si2 cuboctahedra. Both Re–Re bond lengths are 2.58 Å. Both Re–Si bond lengths are 2.56 Å. Si is bonded in a 9-coordinate geometry to four equivalent Pr, four Re, and one Si atom. The Si–Si bond length is 2.52 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(Ga5Mo)8 by Materials Project

Pr(MoGa5)8 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Pr is bonded in a 6-coordinate geometry to two equivalent Mo and twelve Ga atoms. Both Pr–Mo bond lengths are 3.26 Å. There are six shorter (3.08 Å) and six longer (3.73 Å) Pr–Ga bond lengths. There are two inequivalent Mo sites. In the first Mo site, Mo is bonded in a 10-coordinate geometry to one Pr and nine Ga atoms. There are a spread of Mo–Ga bond distances ranging from 2.61–2.65 Å. In the second Mo site, Mo is bonded in a distorted q6 geometry to ten Ga atoms. There are a spread of Mo–Ga bond distances ranging from 2.57–2.70 Å. There are eight inequivalent Ga sites. In the first Ga site, Ga is bonded in a cuboctahedral geometry to twelve Ga atoms. There are six shorter (2.91 Å) and six longer (3.02 Å) Ga–Ga bond lengths. In the second Ga site, Ga is bonded in a distorted linear geometry to two equivalent Mo atoms. In the third Ga site, Ga is bonded in a 2-coordinate geometry to one Pr, two equivalent Mo, and two equivalent Ga atoms. There are one shorter (2.77 Å) and one longer (3.00 Å) Ga–Ga bond lengths. In the fourth Ga site, Ga is bonded in a distorted bent 150 degrees geometry to two equivalent Mo and one Ga atom. In the fifth Ga site, Ga is bonded in a distorted bent 150 degrees geometry to two Mo and one Ga atom. In the sixth Ga site, Ga is bonded in a 2-coordinate geometry to two equivalent Mo and one Ga atom. The Ga–Ga bond length is 2.68 Å. In the seventh Ga site, Ga is bonded in a 2-coordinate geometry to two Mo and two equivalent Ga atoms. There are one shorter (2.75 Å) and one longer (2.90 Å) Ga–Ga bond lengths. In the eighth Ga site, Ga is bonded in a 8-coordinate geometry to one Pr, two Mo, and five Ga atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(ClO2)3 by Materials Project

Pr(O2Cl)3 crystallizes in the monoclinic P2/c space group. The structure is two-dimensional and consists of one Pr(O2Cl)3 sheet oriented in the (0, 1, 0) direction. Pr is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Pr–O bond distances ranging from 2.31–2.65 Å. There are three inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Pr and one Cl atom. The O–Cl bond length is 1.54 Å. In the second O site, O is bonded in a bent 120 degrees geometry to one Pr and one Cl atom. The O–Cl bond length is 1.65 Å. In the third O site, O is bonded in a bent 120 degrees geometry to one Pr and one O atom. The O–O bond length is 1.30 Å. There are two inequivalent Cl sites. In the first Cl site, Cl is bonded in a single-bond geometry to one O atom. In the second Cl site, Cl is bonded in a water-like geometry to two equivalent O atoms.

36 MATERIALS SCIENCE↗