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DOE OSTI2020

Materials Data on PrMn2SiGe by Materials Project

PrMn2GeSi crystallizes in the tetragonal I4mm space group. The structure is three-dimensional. Pr is bonded in a 8-coordinate geometry to eight equivalent Mn, four equivalent Ge, and four equivalent Si atoms. There are four shorter (3.32 Å) and four longer (3.41 Å) Pr–Mn bond lengths. All Pr–Ge bond lengths are 3.12 Å. All Pr–Si bond lengths are 3.13 Å. Mn is bonded to four equivalent Pr, two equivalent Ge, and two equivalent Si atoms to form a mixture of edge, face, and corner-sharing MnPr4Si2Ge2 tetrahedra. Both Mn–Ge bond lengths are 2.46 Å. Both Mn–Si bond lengths are 2.37 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Pr, four equivalent Mn, and one Si atom. The Ge–Si bond length is 2.70 Å. Si is bonded in a 9-coordinate geometry to four equivalent Pr, four equivalent Mn, and one Ge atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrSmCo17 by Materials Project

SmPrCo17 crystallizes in the trigonal R3m space group. The structure is three-dimensional. Sm is bonded in a 10-coordinate geometry to nineteen Co atoms. There are a spread of Sm–Co bond distances ranging from 3.00–3.23 Å. Pr is bonded in a 10-coordinate geometry to nineteen Co atoms. There are a spread of Pr–Co bond distances ranging from 3.00–3.26 Å. There are six inequivalent Co sites. In the first Co site, Co is bonded in a 12-coordinate geometry to one Sm, one Pr, and ten Co atoms. There are a spread of Co–Co bond distances ranging from 2.37–2.65 Å. In the second Co site, Co is bonded to two equivalent Sm, one Pr, and nine Co atoms to form CoPrSm2Co9 cuboctahedra that share corners with fifteen CoPrSm2Co9 cuboctahedra, edges with eight CoPrSmCo10 cuboctahedra, and faces with ten CoPrSm2Co9 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.40–2.58 Å. In the third Co site, Co is bonded to one Sm, two equivalent Pr, and nine Co atoms to form CoPr2SmCo9 cuboctahedra that share corners with fifteen CoPrSm2Co9 cuboctahedra, edges with eight CoPrSmCo10 cuboctahedra, and faces with ten CoPrSm2Co9 cuboctahedra. There are two shorter (2.41 Å) and one longer (2.59 Å) Co–Co bond lengths. In the fourth Co site, Co is bonded to one Sm, one Pr, and ten Co atoms to form CoPrSmCo10 cuboctahedra that share corners with fourteen CoPrSmCo10 cuboctahedra, edges with six CoPrSm2Co9 cuboctahedra, and faces with ten CoPrSm2Co9 cuboctahedra. There are one shorter (2.56 Å) and one longer (2.57 Å) Co–Co bond lengths. In the fifth Co site, Co is bonded in a 2-coordinate geometry to one Pr and thirteen Co atoms. The Co–Co bond length is 2.33 Å. In the sixth Co site, Co is bonded in a 2-coordinate geometry to one Sm and thirteen Co atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrSm(Co2Ni3)2 by Materials Project

SmPr(Co2Ni3)2 crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. Sm is bonded in a 6-coordinate geometry to six Co and twelve Ni atoms. There are two shorter (2.85 Å) and four longer (2.86 Å) Sm–Co bond lengths. There are eight shorter (3.18 Å) and four longer (3.19 Å) Sm–Ni bond lengths. Pr is bonded in a 6-coordinate geometry to six Co and twelve Ni atoms. All Pr–Co bond lengths are 2.87 Å. There are four shorter (3.19 Å) and eight longer (3.20 Å) Pr–Ni bond lengths. There are two inequivalent Co sites. In the first Co site, Co is bonded in a 12-coordinate geometry to two equivalent Sm, one Pr, and six Ni atoms. There are two shorter (2.46 Å) and four longer (2.47 Å) Co–Ni bond lengths. In the second Co site, Co is bonded in a 12-coordinate geometry to one Sm, two equivalent Pr, and six Ni atoms. There are four shorter (2.46 Å) and two longer (2.47 Å) Co–Ni bond lengths. There are three inequivalent Ni sites. In the first Ni site, Ni is bonded to four equivalent Pr, four equivalent Co, and four equivalent Ni atoms to form NiPr4Co4Ni4 cuboctahedra that share corners with sixteen NiPr2Sm2Co4Ni4 cuboctahedra, edges with ten NiPr2Sm2Co4Ni4 cuboctahedra, and faces with ten NiPr4Co4Ni4 cuboctahedra. All Ni–Ni bond lengths are 2.48 Å. In the second Ni site, Ni is bonded to four equivalent Sm, four equivalent Co, and four equivalent Ni atoms to form NiSm4Co4Ni4 cuboctahedra that share corners with sixteen NiPr2Sm2Co4Ni4 cuboctahedra, edges with ten NiPr2Sm2Co4Ni4 cuboctahedra, and faces with ten NiSm4Co4Ni4 cuboctahedra. All Ni–Ni bond lengths are 2.47 Å. In the third Ni site, Ni is bonded to two equivalent Sm, two equivalent Pr, four Co, and four Ni atoms to form a mixture of edge, face, and corner-sharing NiPr2Sm2Co4Ni4 cuboctahedra. There are one shorter (2.47 Å) and one longer (2.49 Å) Ni–Ni bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2Al3Co14 by Materials Project

Pr2Co14Al3 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Pr is bonded in a 10-coordinate geometry to sixteen Co and three equivalent Al atoms. There are a spread of Pr–Co bond distances ranging from 3.02–3.22 Å. All Pr–Al bond lengths are 3.28 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 a spread of Co–Co bond distances ranging from 2.42–2.67 Å. Both Co–Al bond lengths are 2.42 Å. In the second Co site, Co is bonded to three equivalent Pr, seven Co, and two equivalent Al atoms to form a mixture of distorted corner, edge, and face-sharing CoPr3Al2Co7 cuboctahedra. There are two shorter (2.43 Å) and one longer (2.67 Å) Co–Co bond lengths. Both Co–Al bond lengths are 2.45 Å. In the third Co site, Co is bonded in a 5-coordinate geometry to one Pr, ten Co, and three equivalent Al atoms. The Co–Co bond length is 2.29 Å. All Co–Al bond lengths are 2.60 Å. Al is bonded in a 10-coordinate geometry to two equivalent Pr and ten Co atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2FeSi2Ru by Materials Project

Pr2RuFeSi2 crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. Pr is bonded in a 9-coordinate geometry to two equivalent Ru, two equivalent Fe, and five equivalent Si atoms. Both Pr–Ru bond lengths are 3.06 Å. Both Pr–Fe bond lengths are 3.06 Å. There are four shorter (3.13 Å) and one longer (3.63 Å) Pr–Si bond lengths. Ru is bonded in a 12-coordinate geometry to four equivalent Pr, four equivalent Fe, and four equivalent Si atoms. All Ru–Fe bond lengths are 2.94 Å. All Ru–Si bond lengths are 2.39 Å. Fe is bonded to four equivalent Pr, four equivalent Ru, and four equivalent Si atoms to form a mixture of distorted face and corner-sharing FePr4Si4Ru4 cuboctahedra. All Fe–Si bond lengths are 2.39 Å. Si is bonded in a 2-coordinate geometry to five equivalent Pr, two equivalent Ru, and two equivalent Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrErCo17 by Materials Project

ErPrCo17 crystallizes in the trigonal R3m space group. The structure is three-dimensional. Er is bonded in a 4-coordinate geometry to nineteen Co atoms. There are a spread of Er–Co bond distances ranging from 2.97–3.20 Å. Pr is bonded in a 10-coordinate geometry to nineteen Co atoms. There are a spread of Pr–Co bond distances ranging from 2.99–3.27 Å. There are six inequivalent Co sites. In the first Co site, Co is bonded to one Er, one Pr, and ten Co atoms to form a mixture of distorted edge, face, and corner-sharing CoPrErCo10 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.36–2.67 Å. In the second Co site, Co is bonded to one Er, two equivalent Pr, and nine Co atoms to form a mixture of edge, face, and corner-sharing CoPr2ErCo9 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.42–2.61 Å. In the third Co site, Co is bonded to two equivalent Er, one Pr, and nine Co atoms to form a mixture of edge, face, and corner-sharing CoPrEr2Co9 cuboctahedra. There are two shorter (2.39 Å) and one longer (2.57 Å) Co–Co bond lengths. In the fourth Co site, Co is bonded to one Er, one Pr, and ten Co atoms to form distorted CoPrErCo10 cuboctahedra that share corners with twenty-two CoPrErCo10 cuboctahedra, edges with ten CoPr2ErCo9 cuboctahedra, and faces with eighteen CoPrErCo10 cuboctahedra. There are one shorter (2.54 Å) and one longer (2.58 Å) Co–Co bond lengths. In the fifth Co site, Co is bonded in a 2-coordinate geometry to one Er and thirteen Co atoms. The Co–Co bond length is 2.34 Å. In the sixth Co site, Co is bonded in a 2-coordinate geometry to one Pr and thirteen Co atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2Al2Fe15 by Materials Project

Pr2Fe15Al2 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Pr is bonded in a 10-coordinate geometry to eighteen Fe and one Al atom. There are a spread of Pr–Fe bond distances ranging from 3.07–3.37 Å. The Pr–Al bond length is 3.12 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to two equivalent Pr, eight Fe, and two equivalent Al atoms to form distorted FePr2Al2Fe8 cuboctahedra that share corners with twenty-two FePr2Al2Fe8 cuboctahedra, edges with ten FePr3AlFe8 cuboctahedra, and faces with eighteen FePr2Al2Fe8 cuboctahedra. All Fe–Fe bond lengths are 2.46 Å. Both Fe–Al bond lengths are 2.60 Å. In the second Fe site, Fe is bonded to two equivalent Pr, eight Fe, and two equivalent Al atoms to form a mixture of distorted edge, face, and corner-sharing FePr2Al2Fe8 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.45–2.71 Å. Both Fe–Al bond lengths are 2.77 Å. In the third Fe site, Fe is bonded to three equivalent Pr, eight Fe, and one Al atom to form a mixture of distorted edge, face, and corner-sharing FePr3AlFe8 cuboctahedra. Both Fe–Fe bond lengths are 2.50 Å. The Fe–Al bond length is 2.61 Å. Al is bonded in a 6-coordinate geometry to one Pr, twelve Fe, and one Al atom. The Al–Al bond length is 2.57 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SrPr12Al12Si18(N2O)18 by Materials Project

SrPr12Al12Si18(N2O)18 crystallizes in the cubic I-43m space group. The structure is three-dimensional. Sr is bonded in a 12-coordinate geometry to twelve equivalent N atoms. All Sr–N bond lengths are 2.90 Å. Pr is bonded in a 5-coordinate geometry to four N and three O atoms. There are a spread of Pr–N bond distances ranging from 2.45–2.93 Å. There are two shorter (2.48 Å) and one longer (2.58 Å) Pr–O bond lengths. Al is bonded in a rectangular see-saw-like geometry to three N and one O atom. There is one shorter (1.91 Å) and two longer (1.92 Å) Al–N bond length. The Al–O bond length is 2.19 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded to three N and one O atom to form corner-sharing SiN3O tetrahedra. There is two shorter (1.75 Å) and one longer (1.85 Å) Si–N bond length. The Si–O bond length is 1.69 Å. In the second Si site, Si is bonded in a rectangular see-saw-like geometry to four N atoms. There is two shorter (1.75 Å) and two longer (1.78 Å) Si–N bond length. There are three inequivalent N sites. In the first N site, N is bonded to one Pr, one Al, and two equivalent Si atoms to form distorted NPrAlSi2 tetrahedra that share corners with two equivalent NPrAlSi2 tetrahedra and corners with two equivalent OPr4 tetrahedra. In the second N site, N is bonded in a 3-coordinate geometry to one Sr, two equivalent Al, and one Si atom. In the third N site, N is bonded in a 5-coordinate geometry to three equivalent Pr and two Si atoms. There are two inequivalent O sites. In the first O site, O is bonded to four equivalent Pr atoms to form OPr4 tetrahedra that share corners with four equivalent NPrAlSi2 tetrahedra and corners with four equivalent OPr4 tetrahedra. In the second O site, O is bonded in a 1-coordinate geometry to one Pr, one Al, and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrY(Co3Ni2)2 by Materials Project

PrY(Co3Ni2)2 crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. Pr is bonded in a 6-coordinate geometry to ten Co and eight equivalent Ni atoms. There are a spread of Pr–Co bond distances ranging from 2.87–3.19 Å. All Pr–Ni bond lengths are 3.20 Å. Y is bonded in a 6-coordinate geometry to ten Co and eight equivalent Ni atoms. There are a spread of Y–Co bond distances ranging from 2.85–3.19 Å. All Y–Ni bond lengths are 3.14 Å. There are four inequivalent Co sites. In the first Co site, Co is bonded in a 12-coordinate geometry to one Pr, two equivalent Y, two equivalent Co, and four equivalent Ni atoms. Both Co–Co bond lengths are 2.40 Å. All Co–Ni bond lengths are 2.46 Å. In the second Co site, Co is bonded in a 12-coordinate geometry to two equivalent Pr, one Y, two equivalent Co, and four equivalent Ni atoms. Both Co–Co bond lengths are 2.43 Å. All Co–Ni bond lengths are 2.45 Å. In the third Co site, Co is bonded to four equivalent Y, four equivalent Co, and four equivalent Ni atoms to form CoY4Co4Ni4 cuboctahedra that share corners with eight CoY4Co4Ni4 cuboctahedra, corners with eight equivalent NiPr2Y2Co6Ni2 cuboctahedra, edges with two equivalent CoY4Co4Ni4 cuboctahedra, edges with eight equivalent NiPr2Y2Co6Ni2 cuboctahedra, faces with two equivalent CoY4Co4Ni4 cuboctahedra, and faces with eight equivalent NiPr2Y2Co6Ni2 cuboctahedra. All Co–Ni bond lengths are 2.46 Å. In the fourth Co site, Co is bonded to four equivalent Pr, four equivalent Co, and four equivalent Ni atoms to form CoPr4Co4Ni4 cuboctahedra that share corners with eight CoY4Co4Ni4 cuboctahedra, corners with eight equivalent NiPr2Y2Co6Ni2 cuboctahedra, edges with two equivalent CoPr4Co4Ni4 cuboctahedra, edges with eight equivalent NiPr2Y2Co6Ni2 cuboctahedra, faces with two equivalent CoPr4Co4Ni4 cuboctahedra, and faces with eight equivalent NiPr2Y2Co6Ni2 cuboctahedra. All Co–Ni bond lengths are 2.50 Å. Ni is bonded to two equivalent Pr, two equivalent Y, six Co, and two equivalent Ni atoms to form NiPr2Y2Co6Ni2 cuboctahedra that share corners with four CoY4Co4Ni4 cuboctahedra, corners with twelve equivalent NiPr2Y2Co6Ni2 cuboctahedra, edges with four CoY4Co4Ni4 cuboctahedra, edges with six equivalent NiPr2Y2Co6Ni2 cuboctahedra, faces with four CoY4Co4Ni4 cuboctahedra, and faces with six equivalent NiPr2Y2Co6Ni2 cuboctahedra. There are one shorter (2.47 Å) and one longer (2.53 Å) Ni–Ni bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Rb3Pr(Cl3O)2 by Materials Project

Rb3Pr(OCl3)2 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. there are three inequivalent Rb sites. In the first Rb site, Rb is bonded to six Cl atoms to form distorted face-sharing RbCl6 pentagonal pyramids. There are three shorter (3.34 Å) and three longer (3.73 Å) Rb–Cl bond lengths. In the second Rb site, Rb is bonded in a 8-coordinate geometry to one O and seven Cl atoms. The Rb–O bond length is 3.05 Å. There are a spread of Rb–Cl bond distances ranging from 3.17–3.75 Å. In the third Rb site, Rb is bonded in a distorted hexagonal planar geometry to six equivalent Cl atoms. All Rb–Cl bond lengths are 3.27 Å. Pr is bonded in a 2-coordinate geometry to two equivalent O and six Cl atoms. Both Pr–O bond lengths are 2.47 Å. There are a spread of Pr–Cl bond distances ranging from 2.86–2.93 Å. O is bonded in a 2-coordinate geometry to one Rb, one Pr, and one Cl atom. The O–Cl bond length is 2.45 Å. There are four inequivalent Cl sites. In the first Cl site, Cl is bonded in a 5-coordinate geometry to four Rb and one O atom. In the second Cl site, Cl is bonded in a 5-coordinate geometry to four Rb and one Pr atom. In the third Cl site, Cl is bonded in a 5-coordinate geometry to four equivalent Rb and one Pr atom. In the fourth Cl site, Cl is bonded to two Rb and two equivalent Pr atoms to form a mixture of edge and corner-sharing ClRb2Pr2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrIn4Ni by Materials Project

PrNiIn4 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Pr is bonded in a 5-coordinate geometry to two equivalent Ni and thirteen In atoms. Both Pr–Ni bond lengths are 3.46 Å. There are a spread of Pr–In bond distances ranging from 3.27–3.70 Å. Ni is bonded in a 9-coordinate geometry to two equivalent Pr and seven In atoms. There are a spread of Ni–In bond distances ranging from 2.55–2.76 Å. There are three inequivalent In sites. In the first In site, In is bonded in a 10-coordinate geometry to four equivalent Pr and six In atoms. There are four shorter (3.16 Å) and two longer (3.21 Å) In–In bond lengths. In the second In site, In is bonded in a 2-coordinate geometry to three equivalent Pr, one Ni, and four equivalent In atoms. In the third In site, In is bonded in a 12-coordinate geometry to three equivalent Pr, three equivalent Ni, and one In atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2ZnBi4 by Materials Project

Pr2ZnBi4 crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. Pr is bonded in a 10-coordinate geometry to two equivalent Zn and eight Bi atoms. Both Pr–Zn bond lengths are 3.34 Å. There are four shorter (3.36 Å) and four longer (3.50 Å) Pr–Bi bond lengths. Zn is bonded in a distorted body-centered cubic geometry to four equivalent Pr and four equivalent Bi atoms. All Zn–Bi bond lengths are 2.82 Å. There are three inequivalent Bi sites. In the first Bi site, Bi is bonded in a 8-coordinate geometry to four equivalent Pr and four equivalent Bi atoms. All Bi–Bi bond lengths are 3.26 Å. In the second Bi site, Bi is bonded in a 8-coordinate geometry to four equivalent Pr and four equivalent Bi atoms. In the third Bi site, Bi is bonded in a 6-coordinate geometry to four equivalent Pr and two equivalent Zn atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2NiGe3 by Materials Project

Pr2NiGe3 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 Ni and nine Ge atoms to form a mixture of edge and face-sharing PrNi3Ge9 cuboctahedra. All Pr–Ni bond lengths are 3.12 Å. There are three shorter (3.12 Å) and six longer (3.34 Å) Pr–Ge bond lengths. Ni is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent Ge atoms. All Ni–Ge bond lengths are 2.46 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent Ge atoms. All Ge–Ge bond lengths are 2.46 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent Ni atoms. In the third Ge site, Ge is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent Ge atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrIClO13 by Materials Project

PrO7IO2ClO4 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of four oxygen molecules; four ClO4 clusters; and one PrO7I sheet oriented in the (1, 0, 0) direction. In each ClO4 cluster, there are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.44 Å. In the second O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.45 Å. In the third O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.47 Å. In the fourth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.47 Å. Cl is bonded in a tetrahedral geometry to four O atoms. In the PrO7I sheet, Pr is bonded in a 8-coordinate geometry to seven O atoms. There are a spread of Pr–O bond distances ranging from 2.26–2.88 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a water-like geometry to two equivalent I atoms. There are one shorter (2.00 Å) and one longer (2.03 Å) O–I bond lengths. In the second O site, O is bonded in a bent 150 degrees geometry to one Pr and one I atom. The O–I bond length is 1.88 Å. In the third O site, O is bonded in a single-bond geometry to one I atom. The O–I bond length is 1.80 Å. In the fourth O site, O is bonded in a 1-coordinate geometry to one Pr and one O atom. The O–O bond length is 1.24 Å. In the fifth O site, O is bonded in a trigonal planar geometry to two equivalent Pr and one I atom. The O–I bond length is 1.93 Å. In the sixth O site, O is bonded in an L-shaped geometry to one Pr and one O atom. In the seventh O site, O is bonded in a distorted trigonal non-coplanar geometry to two equivalent Pr and one I atom. The O–I bond length is 1.94 Å. I is bonded to six O atoms to form edge-sharing IO6 octahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrMnCoGe2 by Materials Project

PrMnCoGe2 crystallizes in the tetragonal I-4m2 space group. The structure is three-dimensional. Pr is bonded in a 8-coordinate geometry to four equivalent Mn, four equivalent Co, and eight equivalent Ge atoms. All Pr–Mn bond lengths are 3.34 Å. All Pr–Co bond lengths are 3.34 Å. All Pr–Ge bond lengths are 3.17 Å. Mn is bonded to four equivalent Pr, four equivalent Co, and four equivalent Ge atoms to form distorted MnPr4Co4Ge4 tetrahedra that share corners with four equivalent CoPr4Mn4Ge4 cuboctahedra, corners with twelve equivalent MnPr4Co4Ge4 tetrahedra, edges with two equivalent CoPr4Mn4Ge4 cuboctahedra, faces with four equivalent CoPr4Mn4Ge4 cuboctahedra, and faces with four equivalent MnPr4Co4Ge4 tetrahedra. All Mn–Co bond lengths are 2.88 Å. All Mn–Ge bond lengths are 2.43 Å. Co is bonded to four equivalent Pr, four equivalent Mn, and four equivalent Ge atoms to form distorted CoPr4Mn4Ge4 cuboctahedra that share corners with twelve equivalent CoPr4Mn4Ge4 cuboctahedra, corners with four equivalent MnPr4Co4Ge4 tetrahedra, edges with two equivalent MnPr4Co4Ge4 tetrahedra, faces with four equivalent CoPr4Mn4Ge4 cuboctahedra, and faces with four equivalent MnPr4Co4Ge4 tetrahedra. All Co–Ge bond lengths are 2.43 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Pr, two equivalent Mn, two equivalent Co, and one Ge atom. The Ge–Ge bond length is 2.65 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2Mg by Materials Project

MgPr2 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of two MgPr2 sheets oriented in the (1, 0, 0) direction. Mg is bonded in a body-centered cubic geometry to eight Pr atoms. There are a spread of Mg–Pr bond distances ranging from 3.40–3.43 Å. There are two inequivalent Pr sites. In the first Pr site, Pr is bonded in a 4-coordinate geometry to four equivalent Mg atoms. In the second Pr site, Pr is bonded in a 12-coordinate geometry to four equivalent Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2Ga2Co15 by Materials Project

Pr2Co15Ga2 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Pr is bonded in a 10-coordinate geometry to eighteen Co and one Ga atom. There are a spread of Pr–Co bond distances ranging from 2.95–3.34 Å. The Pr–Ga bond length is 3.02 Å. There are three inequivalent Co sites. In the first Co site, Co is bonded to two equivalent Pr, eight Co, and two equivalent Ga atoms to form distorted CoPr2Ga2Co8 cuboctahedra that share corners with fourteen CoPr2Ga2Co8 cuboctahedra, edges with six equivalent CoPr3GaCo8 cuboctahedra, and faces with ten CoPr2Ga2Co8 cuboctahedra. There are four shorter (2.41 Å) and four longer (2.45 Å) Co–Co bond lengths. Both Co–Ga 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 Ga atoms. There are a spread of Co–Co bond distances ranging from 2.42–2.60 Å. Both Co–Ga bond lengths are 2.75 Å. In the third Co site, Co is bonded to three equivalent Pr, eight Co, and one Ga atom to form a mixture of corner, edge, and face-sharing CoPr3GaCo8 cuboctahedra. Both Co–Co bond lengths are 2.48 Å. The Co–Ga bond length is 2.61 Å. Ga is bonded in a 7-coordinate geometry to one Pr, twelve Co, and one Ga atom. The Ga–Ga bond length is 2.62 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Dual Inhibitors of SARS-CoV-2 3CL Protease and Human Cathepsin L Containing Glutamine Isosteres Are Anti-CoV-2 Agents

SARS-CoV-2 3CL protease (Main protease) and human cathepsin L are proteases that play unique roles in the infection of human cells by SARS-CoV-2, the causative agent of COVID-19. Both proteases recognize leucine and other hydrophobic amino acids at the P 2 position of a peptidomimetic inhibitor. At the P 1 position, cathepsin L accepts many amino acid side chains, with a partial preference for phenylalanine, while 3CL-PR protease has a stringent specificity for glutamine or glutamine analogues. We have designed, synthesized, and evaluated peptidomimetic aldehyde dual-target (dual-acting) inhibitors using two peptide scaffolds based on those of two Pfizer 3CL-PR inhibitors, Nirmatrelvir, and PF-835321. Our inhibitors contain glutamine isosteres at the P 1 position, including 2-pyridon-3-yl-alanine, 3-pyridinyl-alanine, and 1,3-oxazo-4-yl-alanine groups. Inhibition constants for these new inhibitors ranged from K i = 0.6–18 nM (cathepsin L) and K i = 2.6–124 nM (3CL-PR), for which inhibitors with the 2-pyridon-3-yl-alanal substituent were the most potent for 3CL-PR. The anti-CoV-2 activity of these inhibitors ranged from EC 50 = 0.47–15 μM. X-ray structures of the peptidomimetic aldehyde inhibitors of 3CL-PR with similar scaffolds all demonstrated the formation of thiohemiacetals with Cys 145 , and hydrogen-bonding interactions with the heteroatoms of the pyridon-3-yl-alanyl group, as well as the nitrogen of the N-terminal indole and its appended carbonyl group at the P 3 position. The absence of these hydrogen bonds for the inhibitors containing the 3-pyridinyl-alanyl and 1,3-oxazo-4-yl-alanyl groups was reflected in the less potent inhibition of the inhibitors with 3CL-PR. In summary, our studies demonstrate the value of a second generation of cysteine protease inhibitors that comprise a single agent that acts on both human cathepsin L and SARS-CoV-2 3CL protease. Such dual-target inhibitors will provide anti-COVID-19 drugs that remain active despite the development of resistance due to mutation of the viral protease. Such dual-target inhibitors are more likely to remain useful therapeutics despite the emergence of inactivating mutations in the viral protease because the human cathepsin L will not develop resistance. This particular dual-target approach is innovative since one of the targets is viral (3CL-PR) required for viral protein maturation and the other is human (hCatL) which enables viral infection.

60 APPLIED LIFE SCIENCES↗