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DOE OSTI2020

Materials Data on LiPr6B3O14 by Materials Project

LiPr6B3O14 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Li1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Li–O bond distances ranging from 2.08–2.66 Å. There are six inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded to seven O2- atoms to form a mixture of distorted edge and corner-sharing PrO7 pentagonal bipyramids. There are a spread of Pr–O bond distances ranging from 2.34–2.55 Å. In the second Pr3+ site, Pr3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Pr–O bond distances ranging from 2.38–2.62 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 2.37–2.91 Å. In the fourth Pr3+ site, Pr3+ is bonded to seven O2- atoms to form a mixture of distorted edge and corner-sharing PrO7 pentagonal bipyramids. There are a spread of Pr–O bond distances ranging from 2.39–2.57 Å. In the fifth Pr3+ site, Pr3+ is bonded to seven O2- atoms to form a mixture of distorted edge and corner-sharing PrO7 pentagonal bipyramids. There are a spread of Pr–O bond distances ranging from 2.39–2.55 Å. In the sixth 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 2.34–2.67 Å. There are three inequivalent B3+ sites. In the first B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.38–1.40 Å. In the second B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.38–1.40 Å. In the third B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.38–1.41 Å. There are fourteen 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 in a distorted single-bond geometry to one Li1+, two Pr3+, and one B3+ atom. In the third O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of edge and corner-sharing OPr4 tetrahedra. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two Pr3+, and one B3+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Li1+, three Pr3+, and one B3+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one Li1+, two Pr3+, and one B3+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two Pr3+, and one B3+ atom. In the eighth O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of distorted edge and corner-sharing OPr4 tetrahedra. In the ninth O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of edge and corner-sharing OPr4 tetrahedra. In the tenth O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of edge and corner-sharing OPr4 tetrahedra. In the eleventh O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of edge and corner-sharing OPr4 tetrahedra. In the twelfth O2- site, O2- is bonded in a distorted single-bond geometry to one Li1+, three Pr3+, and one B3+ atom. In the thirteenth O2- site, O2- is bonded in a distorted single-bond geometry to one Li1+, two Pr3+, and one B3+ atom. In the fourteenth O2- site, O2- is bonded in a distorted single-bond geometry to three Pr3+ and one B3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrCu4Pd by Materials Project

PrCu4Pd crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Pr is bonded in a distorted hexagonal planar geometry to three equivalent Pd and fifteen Cu atoms. All Pr–Pd bond lengths are 2.99 Å. There are three shorter (2.99 Å) and twelve longer (3.35 Å) Pr–Cu bond lengths. Pd is bonded to three equivalent Pr and nine Cu atoms to form distorted PdPr3Cu9 cuboctahedra that share corners with twenty-one CuPr3Cu6Pd3 cuboctahedra, edges with six equivalent PdPr3Cu9 cuboctahedra, faces with two equivalent PdPr3Cu9 cuboctahedra, and faces with twenty-one CuPr3Cu6Pd3 cuboctahedra. There are six shorter (2.61 Å) and three longer (2.99 Å) Pd–Cu bond lengths. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded to three equivalent Pr, three equivalent Pd, and six equivalent Cu atoms to form CuPr3Cu6Pd3 cuboctahedra that share corners with nine equivalent PdPr3Cu9 cuboctahedra, corners with twelve equivalent CuPr4Cu6Pd2 cuboctahedra, edges with six equivalent CuPr3Cu6Pd3 cuboctahedra, faces with three equivalent PdPr3Cu9 cuboctahedra, and faces with twenty CuPr3Cu6Pd3 cuboctahedra. All Cu–Cu bond lengths are 2.57 Å. In the second Cu site, Cu is bonded to four equivalent Pr, two equivalent Pd, and six Cu atoms to form distorted CuPr4Cu6Pd2 cuboctahedra that share corners with four equivalent PdPr3Cu9 cuboctahedra, corners with twenty CuPr3Cu6Pd3 cuboctahedra, edges with ten equivalent CuPr4Cu6Pd2 cuboctahedra, faces with six equivalent PdPr3Cu9 cuboctahedra, and faces with sixteen CuPr3Cu6Pd3 cuboctahedra. There are two shorter (2.53 Å) and two longer (2.65 Å) Cu–Cu bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2(Ga3Ru)3 by Materials Project

Pr2(RuGa3)3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Pr is bonded in a 11-coordinate geometry to eleven Ga atoms. There are a spread of Pr–Ga bond distances ranging from 3.10–3.19 Å. There are two inequivalent Ru sites. In the first Ru site, Ru is bonded in a 8-coordinate geometry to eight Ga atoms. There are a spread of Ru–Ga bond distances ranging from 2.60–2.67 Å. In the second Ru site, Ru is bonded in a 8-coordinate geometry to eight Ga atoms. There are a spread of Ru–Ga bond distances ranging from 2.62–2.66 Å. There are four inequivalent Ga sites. In the first Ga site, Ga is bonded in a 10-coordinate geometry to two equivalent Pr, two equivalent Ru, and six Ga atoms. There are two shorter (2.75 Å) and four longer (2.80 Å) Ga–Ga bond lengths. In the second Ga site, Ga is bonded in a 3-coordinate geometry to three equivalent Pr, three Ru, and five Ga atoms. There are a spread of Ga–Ga bond distances ranging from 2.80–2.97 Å. In the third Ga site, Ga is bonded in a 3-coordinate geometry to two equivalent Pr, three Ru, and five Ga atoms. There are one shorter (2.72 Å) and two longer (2.90 Å) Ga–Ga bond lengths. In the fourth Ga site, Ga is bonded in a 10-coordinate geometry to two equivalent Pr, two equivalent Ru, and six Ga atoms. The Ga–Ga bond length is 2.73 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrCo4Si by Materials Project

PrCo4Si is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Pr is bonded in a 6-coordinate geometry to fourteen Co and four equivalent Si atoms. There are a spread of Pr–Co bond distances ranging from 2.85–3.14 Å. All Pr–Si bond lengths are 3.24 Å. There are two inequivalent Co sites. In the first Co site, Co is bonded in a 12-coordinate geometry to three equivalent Pr, five Co, and two equivalent Si atoms. There are four shorter (2.47 Å) and one longer (2.65 Å) Co–Co bond lengths. Both Co–Si bond lengths are 2.37 Å. In the second Co site, Co is bonded to four equivalent Pr, six Co, and two equivalent Si atoms to form CoPr4Co6Si2 cuboctahedra that share corners with four equivalent SiPr4Co8 cuboctahedra, corners with twelve equivalent CoPr4Co6Si2 cuboctahedra, edges with four equivalent SiPr4Co8 cuboctahedra, edges with six equivalent CoPr4Co6Si2 cuboctahedra, faces with four equivalent SiPr4Co8 cuboctahedra, and faces with six equivalent CoPr4Co6Si2 cuboctahedra. Both Co–Co bond lengths are 2.57 Å. Both Co–Si bond lengths are 2.45 Å. Si is bonded to four equivalent Pr and eight Co atoms to form distorted SiPr4Co8 cuboctahedra that share corners with eight equivalent CoPr4Co6Si2 cuboctahedra, corners with eight equivalent SiPr4Co8 cuboctahedra, edges with two equivalent SiPr4Co8 cuboctahedra, edges with eight equivalent CoPr4Co6Si2 cuboctahedra, faces with two equivalent SiPr4Co8 cuboctahedra, and faces with eight equivalent CoPr4Co6Si2 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrN(ClO)4 by Materials Project

PrN(OCl)4 crystallizes in the orthorhombic P2_12_12 space group. The structure is one-dimensional and consists of two PrN(OCl)4 ribbons oriented in the (1, 0, 0) direction. Pr is bonded in a 6-coordinate geometry to four O and two equivalent Cl atoms. There are two shorter (2.36 Å) and two longer (2.75 Å) Pr–O bond lengths. Both Pr–Cl bond lengths are 2.68 Å. N is bonded in a bent 120 degrees geometry to two equivalent O atoms. Both N–O bond lengths are 1.22 Å. There are two inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to one Pr and one Cl atom. The O–Cl bond length is 1.61 Å. In the second O site, O is bonded in a distorted bent 150 degrees geometry to one Pr and one N atom. There are two inequivalent Cl sites. In the first Cl site, Cl is bonded in a single-bond geometry to one Pr atom. In the second Cl site, Cl is bonded in a single-bond geometry to one O atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2Y by Materials Project

Pr2Y is beta-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Pr is bonded to nine equivalent Pr and three equivalent Y atoms to form PrPr9Y3 cuboctahedra that share corners with six equivalent YPr6Y6 cuboctahedra, corners with nine equivalent PrPr9Y3 cuboctahedra, edges with six equivalent YPr6Y6 cuboctahedra, edges with fifteen equivalent PrPr9Y3 cuboctahedra, faces with seven equivalent YPr6Y6 cuboctahedra, and faces with twelve equivalent PrPr9Y3 cuboctahedra. There are six shorter (3.67 Å) and three longer (3.81 Å) Pr–Pr bond lengths. All Pr–Y bond lengths are 3.63 Å. Y is bonded to six equivalent Pr and six equivalent Y atoms to form YPr6Y6 cuboctahedra that share corners with six equivalent YPr6Y6 cuboctahedra, corners with twelve equivalent PrPr9Y3 cuboctahedra, edges with six equivalent YPr6Y6 cuboctahedra, edges with twelve equivalent PrPr9Y3 cuboctahedra, faces with six equivalent YPr6Y6 cuboctahedra, and faces with fourteen equivalent PrPr9Y3 cuboctahedra. All Y–Y bond lengths are 3.67 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr3Lu by Materials Project

LuPr3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Lu is bonded to twelve equivalent Pr atoms to form LuPr12 cuboctahedra that share corners with six equivalent LuPr12 cuboctahedra, corners with twelve equivalent PrPr8Lu4 cuboctahedra, edges with eighteen equivalent PrPr8Lu4 cuboctahedra, faces with eight equivalent LuPr12 cuboctahedra, and faces with twelve equivalent PrPr8Lu4 cuboctahedra. There are six shorter (3.65 Å) and six longer (3.67 Å) Lu–Pr bond lengths. Pr is bonded to four equivalent Lu and eight equivalent Pr atoms to form PrPr8Lu4 cuboctahedra that share corners with four equivalent LuPr12 cuboctahedra, corners with fourteen equivalent PrPr8Lu4 cuboctahedra, edges with six equivalent LuPr12 cuboctahedra, edges with twelve equivalent PrPr8Lu4 cuboctahedra, faces with four equivalent LuPr12 cuboctahedra, and faces with sixteen equivalent PrPr8Lu4 cuboctahedra. There are a spread of Pr–Pr bond distances ranging from 3.63–3.72 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrNdCo10 by Materials Project

NdPrCo10 crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. Nd is bonded in a 6-coordinate geometry to eighteen Co atoms. There are a spread of Nd–Co bond distances ranging from 2.90–3.21 Å. Pr is bonded in a 6-coordinate geometry to eighteen Co atoms. There are a spread of Pr–Co bond distances ranging from 2.90–3.21 Å. There are five inequivalent Co sites. In the first Co site, Co is bonded in a 12-coordinate geometry to one Nd, two equivalent Pr, and six Co atoms. There are four shorter (2.46 Å) and two longer (2.47 Å) Co–Co bond lengths. In the second Co site, Co is bonded in a 12-coordinate geometry to two equivalent Nd, one Pr, and six Co atoms. All Co–Co bond lengths are 2.46 Å. In the third Co site, Co is bonded to four equivalent Pr and eight Co atoms to form CoPr4Co8 cuboctahedra that share corners with sixteen CoPr2Nd2Co8 cuboctahedra, edges with ten CoPr2Nd2Co8 cuboctahedra, and faces with ten CoPr4Co8 cuboctahedra. All Co–Co bond lengths are 2.52 Å. In the fourth Co site, Co is bonded to four equivalent Nd and eight Co atoms to form CoNd4Co8 cuboctahedra that share corners with sixteen CoPr2Nd2Co8 cuboctahedra, edges with ten CoPr2Nd2Co8 cuboctahedra, and faces with ten CoNd4Co8 cuboctahedra. All Co–Co bond lengths are 2.51 Å. In the fifth Co site, Co is bonded to two equivalent Nd, two equivalent Pr, and eight Co atoms to form a mixture of edge, corner, and face-sharing CoPr2Nd2Co8 cuboctahedra. There are one shorter (2.51 Å) and one longer (2.52 Å) Co–Co bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr3TiCl5O4 by Materials Project

Pr3TiO4Cl5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to two equivalent O2- and seven Cl1- atoms. Both Pr–O bond lengths are 2.27 Å. There are a spread of Pr–Cl bond distances ranging from 2.96–3.28 Å. In the second Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to two equivalent O2- and seven Cl1- atoms. Both Pr–O bond lengths are 2.28 Å. There are a spread of Pr–Cl bond distances ranging from 2.97–3.27 Å. In the third Pr3+ site, Pr3+ is bonded in a distorted bent 120 degrees geometry to two equivalent O2- and seven Cl1- atoms. Both Pr–O bond lengths are 2.29 Å. There are a spread of Pr–Cl bond distances ranging from 3.00–3.42 Å. Ti4+ is bonded to five O2- atoms to form corner-sharing TiO5 trigonal bipyramids. There is three shorter (1.85 Å) and two longer (2.04 Å) Ti–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ti4+ atoms. In the second O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Pr3+, one Ti4+, and one Cl1- atom. The O–Cl bond length is 3.21 Å. In the third O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Pr3+, one Ti4+, and one Cl1- atom. The O–Cl bond length is 3.27 Å. In the fourth O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Pr3+ and one Ti4+ atom. There are five inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 4-coordinate geometry to four Pr3+ and two equivalent Cl1- atoms. Both Cl–Cl bond lengths are 3.35 Å. In the second Cl1- site, Cl1- is bonded in a 7-coordinate geometry to five Pr3+, two O2-, and six Cl1- atoms. There are two shorter (3.46 Å) and two longer (3.49 Å) Cl–Cl bond lengths. In the third Cl1- site, Cl1- is bonded in a 4-coordinate geometry to four Pr3+ and two equivalent Cl1- atoms. In the fourth Cl1- site, Cl1- is bonded in a 4-coordinate geometry to four Pr3+ atoms. In the fifth Cl1- site, Cl1- is bonded in a 4-coordinate geometry to four Pr3+ and two equivalent Cl1- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrFeNi4 by Materials Project

PrNi4Fe crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Pr is bonded in a 6-coordinate geometry to three equivalent Fe and fifteen Ni atoms. All Pr–Fe bond lengths are 2.90 Å. There are three shorter (2.90 Å) and twelve longer (3.20 Å) Pr–Ni bond lengths. Fe is bonded to three equivalent Pr and nine Ni atoms to form distorted FePr3Ni9 cuboctahedra that share corners with twenty-one NiPr3Fe3Ni6 cuboctahedra, edges with six equivalent FePr3Ni9 cuboctahedra, faces with two equivalent FePr3Ni9 cuboctahedra, and faces with twenty-one NiPr3Fe3Ni6 cuboctahedra. There are six shorter (2.45 Å) and three longer (2.90 Å) Fe–Ni bond lengths. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded to three equivalent Pr, three equivalent Fe, and six equivalent Ni atoms to form distorted NiPr3Fe3Ni6 cuboctahedra that share corners with nine equivalent FePr3Ni9 cuboctahedra, corners with twelve equivalent NiPr4Fe2Ni6 cuboctahedra, edges with six equivalent NiPr3Fe3Ni6 cuboctahedra, faces with three equivalent FePr3Ni9 cuboctahedra, and faces with twenty NiPr3Fe3Ni6 cuboctahedra. All Ni–Ni bond lengths are 2.45 Å. In the second Ni site, Ni is bonded to four equivalent Pr, two equivalent Fe, and six Ni atoms to form NiPr4Fe2Ni6 cuboctahedra that share corners with four equivalent FePr3Ni9 cuboctahedra, corners with twenty NiPr3Fe3Ni6 cuboctahedra, edges with ten equivalent NiPr4Fe2Ni6 cuboctahedra, faces with six equivalent FePr3Ni9 cuboctahedra, and faces with sixteen NiPr3Fe3Ni6 cuboctahedra. There are two shorter (2.51 Å) and two longer (2.52 Å) Ni–Ni bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr3CBr5 by Materials Project

Pr3CBr5 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded to two equivalent C4- and five Br1- atoms to form distorted PrC2Br5 pentagonal bipyramids that share a cornercorner with one PrCBr5 octahedra, corners with two equivalent PrC2Br5 pentagonal bipyramids, edges with three equivalent PrCBr5 octahedra, edges with two equivalent PrC2Br5 pentagonal bipyramids, and faces with two equivalent PrC2Br5 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 5°. There are one shorter (2.62 Å) and one longer (2.64 Å) Pr–C bond lengths. There are a spread of Pr–Br bond distances ranging from 2.97–3.23 Å. In the second Pr3+ site, Pr3+ is bonded to two equivalent C4- and five Br1- atoms to form PrC2Br5 pentagonal bipyramids that share corners with two equivalent PrC2Br5 pentagonal bipyramids, edges with three equivalent PrCBr5 octahedra, edges with two equivalent PrC2Br5 pentagonal bipyramids, and faces with two equivalent PrC2Br5 pentagonal bipyramids. There are one shorter (2.63 Å) and one longer (2.65 Å) Pr–C bond lengths. There are three shorter (2.97 Å) and two longer (3.22 Å) Pr–Br bond lengths. In the third Pr3+ site, Pr3+ is bonded to one C4- and five Br1- atoms to form PrCBr5 octahedra that share a cornercorner with one PrC2Br5 pentagonal bipyramid, an edgeedge with one PrCBr5 octahedra, and edges with six PrC2Br5 pentagonal bipyramids. The Pr–C bond length is 2.33 Å. There are a spread of Pr–Br bond distances ranging from 2.90–3.20 Å. C4- is bonded in a 6-coordinate geometry to five Pr3+ and one C4- atom. The C–C bond length is 1.41 Å. There are five inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a distorted T-shaped geometry to three Pr3+ atoms. In the second Br1- site, Br1- is bonded in a distorted see-saw-like geometry to four Pr3+ atoms. In the third Br1- site, Br1- is bonded in a 3-coordinate geometry to three Pr3+ atoms. In the fourth Br1- site, Br1- is bonded in a distorted T-shaped geometry to three Pr3+ atoms. In the fifth Br1- site, Br1- is bonded in an L-shaped geometry to two Pr3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

C–H Bond Activation Facilitated by Bis(phosphinoamide) Heterobimetallic Zr/Co Complexes

The activation of C–H bonds using first-row transition metals poses a formidable challenge in the development of sustainable catalytic methods. Early/late heterobimetallic complexes provide a Lewis acidic binding site for directing groups, facilitating the activation of C–H bonds at an appended first-row transition metal center. In this work, the reactivity of the ZrIV/Co–I heterobimetallic complexes (THF)(I)Zr(XylNP i Pr 2 ) 2 Co(PR 3 ) (1-PR 3 ; Xyl = 3,5-dimethylphenyl; PR 3 = PMe 3 , PPh 2 Me) toward directed C–H bond activation is explored with pyridine and terminal alkyne derivatives. 1-PMe 3 reacts reversibly with 4-methylpyridine to afford the C–H activated complex (4-Me-C 5 H 4 N)(I)Zr(XylNP i Pr 2 ) 2 (μ-4-Me-C 5 H 3 N)Co(PMe 3 )(H) (3-PMe 3 ). By using the more Lewis basic substrate 4-tert-butylpyridine, (I)Zr(XylNP i Pr 2 )2(μ-4- t Bu-C 5 H 3 N)Co(PMe 3 )(H) (4-PMe 3 ) is formed irreversibly. In addition to pyridine derivatives, 1-PPh 2 Me can activate the C–H bond of terminal alkynes to form (THF)(I)Zr(XylNPiPr 2 ) 2 (μ-R'C≡C)Co(PPh 2 Me)(H) (R' = Ph (5-PPh 2 Me); R' = SiMe 3 (6-PPh 2 Me)).

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Increased Crystal Field Drives Intermediate Coupling and Minimizes Decoherence in Tetravalent Praseodymium Qubits

Crystal field (CF) control of rare-earth (RE) ions has been employed to minimize decoherence in qubits and to enhance the effective barrier of single-molecule magnets. The CF approach has been focused on the effects of symmetry on dynamic magnetic properties. Herein, the magnitude of the CF is increased via control of the RE oxidation state. The enhanced 4f metal-ligand covalency in Pr 4+ gives rise to CF energy scales that compete with the spin-orbit coupling of Pr 4+ and thereby shifts the paradigm from the ionic ζ SOC >> V CF limit, used to describe trivalent RE-ion, to an intermediate coupling (IC) regime. We examine Pr 4+ -doped perovskite oxide lattices (BaSnO 3 and BaZrO 3 ). These systems are defined by IC which quenches orbital angular momentum. Therefore, the single-ion spin-orbit coupled states in Pr 4+ can be chemically tuned. We demonstrate a relatively large hyperfine interaction of A iso = 1800 MHz for Pr 4+ , coherent manipulation of the spin with Q M = 2Ω R $T$ m reaching up to ~400 for 0.1Pr:BSO at $T$ = 5 K, and significant improvement of the temperature at which $T$ m is limited by $T$ 1 ($T$* = 60 K) compared to other RE ion qubits.

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

A microbiological survey of handwashing sinks in the hospital built environment reveals differences in patient room and healthcare personnel sinks

Handwashing sinks and their associated premise plumbing are an ideal environment for pathogen-harboring biofilms to grow and spread throughout facilities due to the connected system of wastewater plumbing. This study was designed to understand the distribution of pathogens and antibiotic resistant organisms (ARO) within and among handwashing sinks in healthcare settings, using culture-dependent methods to quantify Pseudomonas aeruginosa, opportunistic pathogens capable of growth on a cefotaxime-containing medium (OPP-C), and carbapenem-resistant Enterobacteriaceae (CRE). Isolates from each medium identified as P. aeruginosa or Enterobacteriaceae were tested for susceptibility to aztreonam, ceftazidime, and meropenem; Enterobacteriaceae were also tested against ertapenem and cefotaxime. Isolates exhibiting resistance or intermediate resistance were designated ARO. Pathogens were quantified at different locations within handwashing sinks and compared in quantity and distribution between healthcare personnel (HCP) and patient room (PR) sinks. ARO were compared between samples within a sink (biofilm vs planktonic samples) and between sink types (HCP vs. PR). The drain cover was identified as a reservoir within multiple sinks that was often colonized by pathogens despite daily sink cleaning. P. aeruginosa and OPP-C mean log 10 CFU/cm 2 counts were higher in p-trap and tail pipe biofilm samples from HCP compared to PR sinks (2.77 ± 2.39 vs. 1.23 ± 1.62 and 5.27 ± 1.10 vs. 4.74 ± 1.06) for P. aeruginosa and OPP-C, respectively. P. aeruginosa and OPP-C mean log 10 CFU/ml counts were also higher (p < 0.05) in HCP compared to PR sinks p-trap water (2.21 ± 1.52 vs. 0.89 ± 1.44 and 3.87 ± 0.78 vs. 3.21 ± 1.11) for P. aeruginosa and OPP-C, respectively. However, a greater percentage of ARO were recovered from PR sinks compared to HCP sinks (p < 0.05) for Enterobacteriaceae (76.4 vs. 32.9%) and P. aeruginosa (25.6 vs. 0.3%). This study supports previous work citing that handwashing sinks are reservoirs for pathogens and ARO and identifies differences in pathogen and ARO quantities between HCP and PR sinks, despite the interconnected premise plumbing.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2024

Large eddy simulation of a supersonic lifted hydrogen flame: Impacts of Lewis, turbulent Schmidt and Prandtl numbers

Parametric large eddy simulations (LES) of a supersonic lifted hydrogen flame are reported. The emphases are on two aspects: impacts of (1) Lewis number (Lei of the ith species) and (2) turbulent Schmidt and Prandtl numbers (⁠Sc t and Pr t ⁠) on supersonic turbulent flame and flow structures. Five cases are considered: species-specific Le i , Sc t = Sr t = 1.0 (C 0 ); unity Le i , Sc t = Pr t = 1.0 (C 1 ); species-specific Sc t = 0.5, Pr t = 1.0 (C 2 ); species-specific Le i , Sc t = 1.0, Pr t = 0.5 (C 3 ); and species-specific Le i , Sc t = Pr t = 0.5 (C 4 ). Numerical results of instantaneous and/or time-averaged species mole fractions, mixture fraction, heat release rate, flame base location, and mixed modes of premixed and diffusion combustion are compared between cases C 0 and C 1 . Differences in auto-ignition locations and strengths and flame structures and stabilization specify the impacts of Lewis number. They are triggered by different predictions of species mass and thermal diffusions at fuel-coflow and/or coflow-ambient air mixing layers. These differences are rationalized by a scale analysis of mass/thermal diffusion and convection for case C 0 , which suggests the relatively low but non-negligible former against the latter. Cases C 0 and C 2 –C 4 barely see differences in terms of instantaneous and/or time-averaged temperature, velocity, and mixed combustion modes except for further downstream areas where combustion occurs. Both Sc t and Pr t impose less significant influences than Lewis number, as sub-grid scale mass/thermal diffusion is subordinate to its resolved counterpart according to their scale analysis for case C 4 .

42 ENGINEERING↗
DOE OSTI2021

Long-term variability of root production in bioenergy crops from ingrowth core measurements

Long-term determination of root biomass production upon land-use conversion to biofuel crops is rare. To assess land-use legacy influences on belowground biomass accumulation, we converted 22-year-old Conservation Reserve Program (CRP) grasslands and 50+-year-old agricultural (AGR) lands to corn (C), switchgrass (Sw) and restored prairie (Pr) biofuel crops. We maintained one CRP grassland as a reference (Ref). We hypothesized that land-use history and crop type have significant effects on root density, with perennial crops on CRP grasslands having a higher root biomass productivity, while corn grown on former agricultural lands produce the lowest root biomass. Methods The ingrowth core method was used to determine in situ ingrowth root biomass, alongside measurements of aboveground net primary productivity (ANPP). Ancillary measurements, including air temperature, growing season length and precipitation were used to examine their influences on root biomass production. Important Findings Root biomass productivity was the highest in unconverted CRP grassland (1716 g m-2 yr-1) and lowest in corn fields (526 g m-2 yr-1). All perennial sites converted from CRP and AGR lands had lower root biomass and ANPP in the first year of planting but peaked in 2011 for switchgrass and a year later for restored prairies. Ecosystem stability was higher in restored prairies (AGR-Pr: 4.3 ± 0.11; CRP-Pr: 4.1 ± 0.10), with all monocultures exhibiting a lower stability. Root biomass production was positively related to ANPP (R2 = 0.40). Overall, attention should be given to root biomass accumulation in large-scale biofuel production as it is a major source of carbon sequestration.

Environmental Sciences & Ecology↗
DOE OSTI2026

Cooperative spin coupling in PrFeO3

A transition from crystal-field to spin wave excitations has been experimentally observed in PrFeO3 using inelastic neutron scattering. Theoretical modeling with density functional theory and the mean field random phase approximation successfully reproduces the experimental observations and allows extraction of the values for the various exchange interactions. The study reveals that the strong coupling between the two magnetic sublattices of Pr and Fe is the fundamental mechanism underlying the low-temperature Pr magnetism. This coupling, analogous to the Dicke cooperative interaction between atoms and photons, polarizes the Pr moments, enhances the Pr-Pr interactions, and contributes to the formation of a quasidoublet, leading to the transition from single-particle to collective excitations within the Pr sublattice. Furthermore, this coupling induces spin reorientation on the Fe sublattice. The manipulation of magnetic moments via spin waves is achievable through the coupling between different magnetic sublattices in a bulk material containing multiple magnetic ions.

Garlea, Vasile [ORNL] (ORCID:0000000253227271)↗
DOE OSTI2022

Electrochemistry of Praseodymium in Aqueous Solution Using a Liquid Gallium Cathode

We report the electrochemistry of liquid Ga electrodes in aqueous media was examined in the presence of praseodymium acetate (PrOAc) as an alternate path for low temperature reduction of rare earth elements (REE). This study investigated the aqueous electrochemistry of Ga with and without REEs (Pr). Cyclic voltammetry experiments showed that in the presence of PrOAc, an order of magnitude increase in cathodic current was observed for the Ga electrode, compared to that in the absence of Pr. Decrease in the reduction current with the increase of scan rate, with and without Pr, suggests catalytic reactions following electron transfer, which was attributed to the Ga 2 O disproportionation reaction. Chronoamperometric experiments performed in Pr containing solutions formed a precipitate. Over 50% of the Pr ions from the aqueous electrolyte were immobilized in the precipitate; a solid Ga-rich phase. Formation of this precipitate was only possible when Ga oxidation was induced. This condition was achieved by circulation of liquid Ga from the pool via external pump and returned dropwise to the liquid Ga pool. When the collected precipitate was leached in dilute HCl, Pr was released with H 2 evolved as a byproduct, and Ga returned to its initial liquid metallic state. These preliminary results show encouraging new routes that could be applied for the recovery of diluted REE leachates, such as those obtained from magnets, coal fly ash, and ores.

25 ENERGY STORAGE↗