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At least 649 records · Page 36
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Pr2Te(Mo3O23)2 by Materials Project

Pr2Te(MoO7)6(O2)2 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of two oxygen molecules and one Pr2Te(MoO7)6 sheet oriented in the (0, 0, 1) direction. In the Pr2Te(MoO7)6 sheet, Pr is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Pr–O bond distances ranging from 2.21–2.80 Å. There are three inequivalent Mo sites. In the first Mo site, Mo is bonded in a 4-coordinate geometry to six O atoms. There are a spread of Mo–O bond distances ranging from 1.72–2.59 Å. In the second Mo site, Mo is bonded in a 4-coordinate geometry to six O atoms. There are a spread of Mo–O bond distances ranging from 1.71–2.55 Å. In the third Mo site, Mo is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Mo–O bond distances ranging from 1.72–2.38 Å. Te is bonded in an octahedral geometry to six O atoms. There are a spread of Te–O bond distances ranging from 1.91–2.12 Å. There are twenty-one inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.23 Å. In the second O site, O is bonded in a single-bond geometry to one Mo atom. In the third O site, O is bonded in a distorted trigonal non-coplanar geometry to two Mo and one Te atom. In the fourth O site, O is bonded in a linear geometry to one Pr and one Mo atom. In the fifth O site, O is bonded in a distorted bent 150 degrees geometry to one Pr and one O atom. The O–O bond length is 1.41 Å. In the sixth O site, O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.24 Å. In the seventh O site, O is bonded in a bent 120 degrees geometry to two Mo atoms. In the eighth O site, O is bonded in a bent 150 degrees geometry to one Pr and one Mo atom. In the ninth O site, O is bonded in a bent 120 degrees geometry to two O atoms. There is one shorter (1.26 Å) and one longer (1.35 Å) O–O bond length. In the tenth O site, O is bonded in a single-bond geometry to one Mo atom. In the eleventh O site, O is bonded in a bent 120 degrees geometry to one Pr and one O atom. The O–O bond length is 1.24 Å. In the twelfth O site, O is bonded in a bent 120 degrees geometry to one Pr and one O atom. In the thirteenth O site, O is bonded in a bent 120 degrees geometry to one Pr and one O atom. In the fourteenth O site, O is bonded in a single-bond geometry to one Mo atom. In the fifteenth O site, O is bonded in a distorted rectangular see-saw-like geometry to two Mo, one Te, and one O atom. In the sixteenth O site, O is bonded in a bent 120 degrees geometry to two Mo atoms. In the seventeenth O site, O is bonded in a 3-coordinate geometry to two Mo and one Te atom. In the eighteenth O site, O is bonded in a single-bond geometry to one Mo atom. In the nineteenth O site, O is bonded in an L-shaped geometry to one Pr and one O atom. In the twentieth O site, O is bonded in a bent 120 degrees geometry to two Mo atoms. In the twenty-first O site, O is bonded in a single-bond geometry to one O atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrSi2Ir3 by Materials Project

PrIr3Si2 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to two equivalent Pr, twelve Ir, and six equivalent Si atoms. Both Pr–Pr bond lengths are 3.65 Å. There are a spread of Pr–Ir bond distances ranging from 3.18–3.56 Å. There are a spread of Pr–Si bond distances ranging from 3.19–3.38 Å. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 12-coordinate geometry to four equivalent Pr and four equivalent Si atoms. All Ir–Si bond lengths are 2.49 Å. In the second Ir site, Ir is bonded in a 4-coordinate geometry to four equivalent Pr and four equivalent Si atoms. There are two shorter (2.45 Å) and two longer (2.46 Å) Ir–Si bond lengths. Si is bonded in a 10-coordinate geometry to three equivalent Pr and six Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb2Pr2O5 by Materials Project

Tb2Pr2O5 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Tb is bonded to five O atoms to form TbO5 square pyramids that share corners with five equivalent TbO5 square pyramids and faces with four equivalent PrO12 cuboctahedra. There are one shorter (2.12 Å) and four longer (2.20 Å) Tb–O bond lengths. There are two inequivalent Pr sites. In the first Pr site, Pr is bonded in a body-centered cubic geometry to eight equivalent O atoms. All Pr–O bond lengths are 2.90 Å. In the second Pr site, Pr is bonded to twelve O atoms to form PrO12 cuboctahedra that share corners with four equivalent PrO12 cuboctahedra, faces with four equivalent PrO12 cuboctahedra, and faces with eight equivalent TbO5 square pyramids. There are eight shorter (3.01 Å) and four longer (3.11 Å) Pr–O bond lengths. There are two inequivalent O sites. In the first O site, O is bonded to two equivalent Tb and four Pr atoms to form a mixture of distorted corner, edge, and face-sharing OTb2Pr4 octahedra. The corner-sharing octahedra tilt angles range from 0–65°. In the second O site, O is bonded in a linear geometry to two equivalent Tb and four equivalent Pr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Adaptations for gas exchange enabled the elongation of lepidopteran proboscises

The extensive biodiversification of butterflies and moths (Lepidoptera) is partly attributed to their unique mouthparts (proboscis [Pr]) that can span in length from less than 1 mm to over 280mm in Darwin's sphinx moths. Lepi-doptera, similar to other insects, are believed to inhale and exhale respiratory gases only through valve-like spi-racles on their thorax and abdomen, making gas exchange through the narrow tracheae (Tr) challenging for the elongated Pr. How Lepidoptera overcome distance effects for gas transport to the Pr is an open question that is important to understanding how the Pr elongated over evolutionary time. Here, we show with scanning electron microscopy and X-ray imaging that distance effects on gas exchange are overcome by previously unreported micropores on the Pr surface and by superhydrophobic Tr that prevent water loss and entry. We find that the density of micropores decreases monotonically along the Pr length with the maxima proportional to the Pr length and that micropore diameters produce a Knudsen number at the boundary between the slip and transition flow regimes. By numerical estimation, we further show that the respiratory gas exchange for the Pr predominantly occurs via diffusion through the micropores. In conclusion, these adaptations are key innovations vital to Pr elongation, which likely facilitated lepidopteran biodiversification and the radiation of angiosperms by coevolutionary processes.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2023

The Development of the Pooled Rideshare Acceptance Model (PRAM)

Due to the advancements in real-time information communication technologies and sharing economies, rideshare services have gained significant momentum by offering dynamic and/or on-demand services. Rideshare service companies evolved from personal rideshare, where riders traveled solo or with known individuals, into pooled rideshare (PR), where riders can travel with one to multiple unknown riders. Similar to other shared economy services, pooled rideshare is beneficial as it efficiently utilizes resources, resulting in reduced energy usage, as well as reduced costs for the riders. However, previous research has demonstrated that riders have concerns about using pooled rideshare, especially regarding personal safety. A U.S. national survey with 5385 participants was used to understand human factor-related barriers and user preferences to develop a novel Pooled Rideshare Acceptance Model (PRAM). This model used a covariance-based structural equation model (CB-SEM) to identify the relationships between willingness to consider PR factors (time/cost, privacy, safety, service experience, and traffic/environment) and optimizing one’s experience of PR factors (vehicle technology/accessibility, convenience, comfort/ease of use, and passenger safety), resulting in the higher-order factor trust service. We examined the factors’ relative contribution to one’s willingness/attitude towards PR and user acceptance of PR. Privacy, safety, trust service, and convenience were statistically significant factors in the model, as were the comfort/ease of use factor and the service experience, traffic/environment, and passenger safety factors. The only two non-significant factors in the model were time/cost and vehicle technology/accessibility; it is only when a rider feels safe that individuals then consider the additional non-significant variables of time, cost, technology, and accessibility. Privacy, safety, and service experience were factors that discouraged the use of PR, whereas the convenience factor greatly encouraged the acceptance of PR. Despite the time/cost factor’s lack of significance, individual items related to time and cost were crucial when viewed within the context of convenience. This highlights that while user perceptions of privacy and safety are paramount to their attitude towards PR, once safety concerns are addressed, and services are deemed convenient, time and cost elements significantly enhance their trust in pooled rideshare services. This study provides a comprehensive understanding of user acceptance of PR services and offers actionable insights for policymakers and rideshare companies to improve their services and increase user adoption.

dynamic rideshare system↗
DOE OSTI2025

Understanding and Modeling Pooled Rideshare Acceptance: Influential Factors, Preferred User Experiences, and Implications

This dissertation explores factors influencing pooled rideshare (PR) adoption to provide actionable insights for transportation network companies (TNCs) and policymakers. PR allows travelers to share rides with unknown passengers, offering benefits such as cost reduction and congestion relief. However, adoption remains limited due to safety concerns, privacy issues, and trust in rideshare platforms. A national U.S. survey with 5,385 respondents examined transportation preferences and barriers to PR adoption. Exploratory and confirmatory factor analyses identified five key factors influencing PR consideration—safety, service experience, privacy, traffic/environment, and time/cost. Second factor analyses examined ways to optimize PR experiences, revealing four factors—comfort/ease of use, convenience, vehicle technology/accessibility, and passenger safety. Privacy concerns, for instance, using regression analysis, were found to reduce the likelihood of PR adoption by 77%, and convenience had the potential to increase it by 156%. The Pooled Rideshare Acceptance Model (PRAM), based on the Technology Acceptance Model, assessed the impact of these factors using the Structural Equation Model (SEM). Privacy, safety, trust, and convenience had a large effect (Cohen's f2 > 0.35) on PR acceptance, while multigroup analyses (PRAMMA) explored 16 demographic variables such as gender, generation, and income, emphasizing the need for tailored strategies. Based on all the statistical analysis and workshops using descriptive statistics, 95 actionable recommendations were made from the riders' perspective. Findings highlight the importance of customized services, user experience improvements, and policy interventions to enhance PR adoption. This dissertation provides a roadmap for future research and policy development, ensuring evidence-based, practical strategies to improve PR services in the U.S. and beyond.

Gangadharaiah, Rakesh↗
DOE OSTI2020

Materials Data on PrB2Ir3 by Materials Project

PrIr3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to two equivalent Pr, twelve equivalent Ir, and six equivalent B atoms. Both Pr–Pr bond lengths are 3.18 Å. All Pr–Ir bond lengths are 3.19 Å. All Pr–B bond lengths are 3.20 Å. Ir is bonded in a distorted square co-planar geometry to four equivalent Pr and four equivalent B atoms. All Ir–B bond lengths are 2.25 Å. B is bonded in a 6-coordinate geometry to three equivalent Pr and six equivalent Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrPIr by Materials Project

PrIrP is hexagonal omega structure-derived structured and crystallizes in the tetragonal I4_1md space group. The structure is three-dimensional. Pr is bonded to six Ir and six equivalent P atoms to form a mixture of edge and face-sharing PrP6Ir6 cuboctahedra. There are two shorter (3.10 Å) and four longer (3.19 Å) Pr–Ir bond lengths. There are four shorter (3.14 Å) and two longer (3.21 Å) Pr–P bond lengths. There are three inequivalent Ir sites. In the first Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent P atoms. There are two shorter (2.38 Å) and one longer (2.39 Å) Ir–P bond lengths. In the second Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent P atoms. There are two shorter (2.38 Å) and one longer (2.39 Å) Ir–P bond lengths. In the third Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent P atoms. There are two shorter (3.10 Å) and four longer (3.19 Å) Ir–Pr bond lengths. There are two shorter (2.38 Å) and one longer (2.39 Å) Ir–P bond lengths. P is bonded in a 9-coordinate geometry to six equivalent Pr and three Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr5Ge3 by Materials Project

Pr5Ge3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Pr sites. In the first Pr site, Pr is bonded in a 3-coordinate geometry to five equivalent Ge atoms. There are a spread of Pr–Ge bond distances ranging from 3.07–3.65 Å. In the second Pr site, Pr is bonded in a 6-coordinate geometry to six equivalent Ge atoms. All Pr–Ge bond lengths are 3.23 Å. Ge is bonded in a 9-coordinate geometry to nine Pr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2Au by Materials Project

Pr2Au is Cotunnite structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Pr sites. In the first Pr site, Pr is bonded in a 3-coordinate geometry to three equivalent Au atoms. There are one shorter (3.08 Å) and two longer (3.25 Å) Pr–Au bond lengths. In the second Pr site, Pr is bonded to four equivalent Au atoms to form a mixture of distorted edge and corner-sharing PrAu4 tetrahedra. There are a spread of Pr–Au bond distances ranging from 3.03–3.20 Å. Au is bonded in a 7-coordinate geometry to seven Pr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrB2Rh3 by Materials Project

PrRh3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to two equivalent Pr, twelve equivalent Rh, and six equivalent B atoms. Both Pr–Pr bond lengths are 3.12 Å. All Pr–Rh bond lengths are 3.18 Å. All Pr–B bond lengths are 3.20 Å. Rh is bonded in a distorted square co-planar geometry to four equivalent Pr and four equivalent B atoms. All Rh–B bond lengths are 2.23 Å. B is bonded in a 6-coordinate geometry to three equivalent Pr and six equivalent Rh atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2Co3Ge5 by Materials Project

Pr2Co3Ge5 crystallizes in the orthorhombic Ibam space group. The structure is three-dimensional. Pr is bonded in a 1-coordinate geometry to seven Co and ten Ge atoms. There are a spread of Pr–Co bond distances ranging from 3.13–3.44 Å. There are a spread of Pr–Ge bond distances ranging from 2.95–3.29 Å. There are two inequivalent Co sites. In the first Co site, Co is bonded in a 5-coordinate geometry to five equivalent Pr and five Ge atoms. There are a spread of Co–Ge bond distances ranging from 2.36–2.44 Å. In the second Co site, Co is bonded in a 12-coordinate geometry to four equivalent Pr and four equivalent Ge atoms. All Co–Ge bond lengths are 2.44 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 2-coordinate geometry to four equivalent Pr, two equivalent Co, and two equivalent Ge atoms. Both Ge–Ge bond lengths are 2.69 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent Pr, three Co, and two equivalent Ge atoms. In the third Ge site, Ge is bonded in a 8-coordinate geometry to four equivalent Pr and four equivalent Co atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2SbO5F by Materials Project

Pr2SbO5F crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are four inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to six O2- and two equivalent F1- atoms. There are a spread of Pr–O bond distances ranging from 2.42–2.53 Å. There are one shorter (2.46 Å) and one longer (2.72 Å) Pr–F bond lengths. In the second Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to six O2- and two equivalent F1- atoms. There are a spread of Pr–O bond distances ranging from 2.43–2.53 Å. There are one shorter (2.47 Å) and one longer (2.64 Å) Pr–F bond lengths. In the third Pr3+ site, Pr3+ is bonded in a 9-coordinate geometry to seven O2- and two F1- atoms. There are a spread of Pr–O bond distances ranging from 2.48–2.78 Å. There are one shorter (2.47 Å) and one longer (2.74 Å) Pr–F bond lengths. In the fourth Pr3+ site, Pr3+ is bonded in a 9-coordinate geometry to seven O2- and two F1- atoms. There are a spread of Pr–O bond distances ranging from 2.47–2.69 Å. There are one shorter (2.46 Å) and one longer (2.76 Å) Pr–F bond lengths. There are two inequivalent Sb5+ sites. In the first Sb5+ site, Sb5+ is bonded to six O2- atoms to form edge-sharing SbO6 octahedra. There are a spread of Sb–O bond distances ranging from 1.96–2.10 Å. In the second Sb5+ site, Sb5+ is bonded to six O2- atoms to form edge-sharing SbO6 octahedra. There are a spread of Sb–O bond distances ranging from 1.96–2.10 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Pr3+ and two Sb5+ atoms. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three Pr3+ and one Sb5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two Pr3+ and one Sb5+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Pr3+ and two Sb5+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Pr3+ and one Sb5+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to three Pr3+ and one Sb5+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to three Pr3+ and one Sb5+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to three Pr3+ and one Sb5+ atom. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to two Pr3+ and one Sb5+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to three Pr3+ and one Sb5+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a 2-coordinate geometry to four Pr3+ atoms. In the second F1- site, F1- is bonded in a 2-coordinate geometry to four Pr3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr4S3N2 by Materials Project

Pr4N2S3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are four inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded in a 6-coordinate geometry to two N3- and four S2- atoms. There are one shorter (2.35 Å) and one longer (2.39 Å) Pr–N bond lengths. There are a spread of Pr–S bond distances ranging from 2.88–2.94 Å. In the second Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to two N3- and five S2- atoms. There are one shorter (2.36 Å) and one longer (2.41 Å) Pr–N bond lengths. There are a spread of Pr–S bond distances ranging from 3.03–3.48 Å. In the third Pr3+ site, Pr3+ is bonded in a 6-coordinate geometry to two N3- and four S2- atoms. There are one shorter (2.37 Å) and one longer (2.39 Å) Pr–N bond lengths. There are a spread of Pr–S bond distances ranging from 2.92–2.97 Å. In the fourth Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to two N3- and five S2- atoms. There are one shorter (2.32 Å) and one longer (2.37 Å) Pr–N bond lengths. There are a spread of Pr–S bond distances ranging from 3.05–3.34 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded to four Pr3+ atoms to form NPr4 tetrahedra that share corners with two SPr6 octahedra, corners with two equivalent NPr4 tetrahedra, edges with two SPr6 octahedra, and an edgeedge with one NPr4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–50°. In the second N3- site, N3- is bonded to four Pr3+ atoms to form NPr4 tetrahedra that share corners with two SPr6 octahedra, corners with two equivalent NPr4 tetrahedra, edges with two SPr6 octahedra, and an edgeedge with one NPr4 tetrahedra. The corner-sharing octahedra tilt angles range from 33–59°. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 6-coordinate geometry to six Pr3+ atoms. In the second S2- site, S2- is bonded to six Pr3+ atoms to form distorted SPr6 octahedra that share corners with four NPr4 tetrahedra, edges with two equivalent SPr6 octahedra, and edges with four NPr4 tetrahedra. In the third S2- site, S2- is bonded in a 6-coordinate geometry to six Pr3+ atoms. In the fourth S2- site, S2- is bonded to six Pr3+ atoms to form distorted SPr6 octahedra that share corners with four NPr4 tetrahedra, edges with two equivalent SPr6 octahedra, and edges with four NPr4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrCu6 by Materials Project

PrCu6 crystallizes in the monoclinic P2_1/c 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 2.89–3.40 Å. There are six inequivalent Cu sites. In the first 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 2.45–3.06 Å. In the second Cu site, Cu is bonded to three equivalent Pr and nine Cu atoms to form a mixture of distorted corner, edge, and face-sharing CuPr3Cu9 cuboctahedra. There are a spread of Cu–Cu bond distances ranging from 2.48–2.69 Å. In the third 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 2.53–3.25 Å. In the fourth Cu site, Cu is bonded to three equivalent Pr and nine Cu atoms to form a mixture of distorted corner, edge, and face-sharing CuPr3Cu9 cuboctahedra. There are a spread of Cu–Cu bond distances ranging from 2.45–2.62 Å. In the fifth Cu site, Cu is bonded in a 12-coordinate geometry to three equivalent Pr and nine Cu atoms. There are one shorter (2.56 Å) and one longer (3.22 Å) Cu–Cu bond lengths. In the sixth Cu site, Cu is bonded to three equivalent Pr and nine Cu atoms to form a mixture of corner, edge, and face-sharing CuPr3Cu9 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaPr4I7N2 by Materials Project

NaPr4N2I7 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. Na1+ is bonded in a distorted octahedral geometry to six I1- atoms. There are a spread of Na–I bond distances ranging from 3.08–3.52 Å. There are four inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to two N3- and four I1- atoms. Both Pr–N bond lengths are 2.33 Å. There are a spread of Pr–I bond distances ranging from 3.18–3.47 Å. In the second Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to two N3- and four I1- atoms. Both Pr–N bond lengths are 2.34 Å. There are a spread of Pr–I bond distances ranging from 3.15–3.42 Å. In the third Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to two N3- and four I1- atoms. There are one shorter (2.35 Å) and one longer (2.36 Å) Pr–N bond lengths. There are a spread of Pr–I bond distances ranging from 3.24–3.76 Å. In the fourth Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to two N3- and four I1- atoms. Both Pr–N bond lengths are 2.36 Å. There are a spread of Pr–I bond distances ranging from 3.24–3.73 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded to four Pr3+ atoms to form edge-sharing NPr4 tetrahedra. In the second N3- site, N3- is bonded to four Pr3+ atoms to form edge-sharing NPr4 tetrahedra. There are seven inequivalent I1- sites. In the first I1- site, I1- is bonded in a 3-coordinate geometry to one Na1+ and two Pr3+ atoms. In the second I1- site, I1- is bonded in a 4-coordinate geometry to one Na1+ and three Pr3+ atoms. In the third I1- site, I1- is bonded in a 2-coordinate geometry to two Pr3+ atoms. In the fourth I1- site, I1- is bonded in a 4-coordinate geometry to one Na1+ and three Pr3+ atoms. In the fifth I1- site, I1- is bonded in a 3-coordinate geometry to one Na1+ and two Pr3+ atoms. In the sixth I1- site, I1- is bonded in a 3-coordinate geometry to one Na1+ and two Pr3+ atoms. In the seventh I1- site, I1- is bonded in a distorted T-shaped geometry to one Na1+ and two Pr3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrB2Ru3 by Materials Project

PrRu3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to two equivalent Pr, twelve equivalent Ru, and six equivalent B atoms. Both Pr–Pr bond lengths are 3.05 Å. All Pr–Ru bond lengths are 3.18 Å. All Pr–B bond lengths are 3.23 Å. Ru is bonded in a distorted square co-planar geometry to four equivalent Pr and four equivalent B atoms. All Ru–B bond lengths are 2.22 Å. B is bonded in a 6-coordinate geometry to three equivalent Pr and six equivalent Ru atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2Ga by Materials Project

Pr2Ga is Cotunnite structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Pr sites. In the first Pr site, Pr is bonded in a 4-coordinate geometry to five equivalent Ga atoms. There are a spread of Pr–Ga bond distances ranging from 3.20–3.72 Å. In the second Pr site, Pr is bonded in a 5-coordinate geometry to five equivalent Ga atoms. There are a spread of Pr–Ga bond distances ranging from 3.23–3.49 Å. Ga is bonded in a 10-coordinate geometry to ten Pr atoms.

36 MATERIALS SCIENCE↗