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DOE OSTI2020

Materials Data on Th7Ru3 by Materials Project

Th7Ru3 crystallizes in the hexagonal P6_3mc space group. The structure is three-dimensional. there are three inequivalent Th sites. In the first Th site, Th is bonded in a distorted water-like geometry to two equivalent Ru atoms. Both Th–Ru bond lengths are 2.85 Å. In the second Th site, Th is bonded in a 3-coordinate geometry to three equivalent Ru atoms. There are two shorter (2.86 Å) and one longer (3.06 Å) Th–Ru bond lengths. In the third Th site, Th is bonded in a 3-coordinate geometry to three equivalent Ru atoms. All Th–Ru bond lengths are 2.97 Å. Ru is bonded in a 6-coordinate geometry to six Th atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThU3Re8 by Materials Project

U3ThRe8 is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are three inequivalent U sites. In the first U site, U is bonded in a 5-coordinate geometry to one U, three equivalent Th, and twelve Re atoms. The U–U bond length is 2.94 Å. There are one shorter (3.23 Å) and two longer (3.52 Å) U–Th bond lengths. There are a spread of U–Re bond distances ranging from 2.94–3.40 Å. In the second U site, U is bonded in a 8-coordinate geometry to one U, one Th, and twelve Re atoms. The U–U bond length is 3.08 Å. The U–Th bond length is 3.19 Å. There are a spread of U–Re bond distances ranging from 3.03–3.35 Å. In the third U site, U is bonded in a 8-coordinate geometry to two U and twelve Re atoms. There are a spread of U–Re bond distances ranging from 3.00–3.33 Å. Th is bonded in a 8-coordinate geometry to four U and twelve Re atoms. There are a spread of Th–Re bond distances ranging from 3.05–3.35 Å. There are six inequivalent Re sites. In the first Re site, Re is bonded to three equivalent U, three equivalent Th, and six Re atoms to form distorted ReTh3U3Re6 cuboctahedra that share corners with twelve ReTh2U4Re6 cuboctahedra, edges with six equivalent ReTh3U3Re6 cuboctahedra, and faces with twenty ReU6Re6 cuboctahedra. There are a spread of Re–Re bond distances ranging from 2.63–2.79 Å. In the second Re site, Re is bonded to six U and six Re atoms to form ReU6Re6 cuboctahedra that share corners with twelve ReTh2U4Re6 cuboctahedra, edges with six equivalent ReU6Re6 cuboctahedra, and faces with twenty ReTh3U3Re6 cuboctahedra. There are a spread of Re–Re bond distances ranging from 2.61–2.70 Å. In the third Re site, Re is bonded to four U, two equivalent Th, and six Re atoms to form ReTh2U4Re6 cuboctahedra that share corners with eighteen ReTh3U3Re6 cuboctahedra, edges with six ReTh2U4Re6 cuboctahedra, and faces with eighteen ReTh3U3Re6 cuboctahedra. There are two shorter (2.56 Å) and two longer (2.73 Å) Re–Re bond lengths. In the fourth Re site, Re is bonded to five U, one Th, and six Re atoms to form ReThU5Re6 cuboctahedra that share corners with eighteen ReTh3U3Re6 cuboctahedra, edges with six ReTh2U4Re6 cuboctahedra, and faces with eighteen ReTh3U3Re6 cuboctahedra. There are two shorter (2.59 Å) and two longer (2.70 Å) Re–Re bond lengths. In the fifth Re site, Re is bonded to four U, two equivalent Th, and six Re atoms to form distorted ReTh2U4Re6 cuboctahedra that share corners with eighteen ReTh3U3Re6 cuboctahedra, edges with six ReThU5Re6 cuboctahedra, and faces with eighteen ReTh3U3Re6 cuboctahedra. There are one shorter (2.89 Å) and one longer (2.99 Å) Re–Re bond lengths. In the sixth Re site, Re is bonded to five U, one Th, and six Re atoms to form distorted ReThU5Re6 cuboctahedra that share corners with eighteen ReTh3U3Re6 cuboctahedra, edges with six ReTh2U4Re6 cuboctahedra, and faces with eighteen ReTh3U3Re6 cuboctahedra. There are one shorter (2.89 Å) and one longer (2.99 Å) Re–Re bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThMo2O9 by Materials Project

ThMo2O9 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Th is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Th–O bond distances ranging from 2.40–2.51 Å. There are two inequivalent Mo sites. In the first Mo site, Mo is bonded in a tetrahedral geometry to four O atoms. There are a spread of Mo–O bond distances ranging from 1.78–1.81 Å. In the second Mo site, Mo is bonded in a tetrahedral geometry to four O atoms. There is three shorter (1.79 Å) and one longer (1.81 Å) Mo–O bond length. There are nine inequivalent O sites. In the first O site, O is bonded in a distorted linear geometry to one Th and one Mo atom. In the second O site, O is bonded in a single-bond geometry to one Th atom. In the third O site, O is bonded in a distorted linear geometry to one Th and one Mo atom. In the fourth O site, O is bonded in a bent 150 degrees geometry to one Th and one Mo atom. In the fifth O site, O is bonded in a distorted bent 150 degrees geometry to one Th and one Mo atom. In the sixth O site, O is bonded in a distorted bent 150 degrees geometry to one Th and one Mo atom. In the seventh O site, O is bonded in a distorted bent 150 degrees geometry to one Th and one Mo atom. In the eighth O site, O is bonded in a distorted bent 150 degrees geometry to one Th and one Mo atom. In the ninth O site, O is bonded in a distorted bent 150 degrees geometry to one Th and one Mo atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThN3O14 by Materials Project

ThN3O14 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two ThN3O14 clusters. Th is bonded in a 10-coordinate geometry to ten O atoms. There are a spread of Th–O bond distances ranging from 2.28–3.16 Å. There are three inequivalent N sites. In the first N site, N is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.21 Å) and two longer (1.30 Å) N–O bond length. In the second N site, N is bonded in a trigonal planar geometry to three O atoms. There are a spread of N–O bond distances ranging from 1.21–1.31 Å. In the third N site, N is bonded in a trigonal planar geometry to three O atoms. There are a spread of N–O bond distances ranging from 1.21–1.32 Å. There are fourteen inequivalent O sites. In the first O site, O is bonded in a distorted L-shaped geometry to one Th and one N atom. In the second 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 third O site, O is bonded in a single-bond geometry to one N atom. In the fourth O site, O is bonded in a 3-coordinate geometry to two equivalent Th and one O atom. The O–O bond length is 1.52 Å. In the fifth O site, O is bonded in a water-like geometry to one Th and one N atom. In the sixth O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the seventh O site, O is bonded in a distorted bent 120 degrees geometry to one Th and one O atom. In the eighth O site, O is bonded in a distorted water-like geometry to one Th and one N atom. In the ninth O site, O is bonded in a single-bond geometry to one N atom. In the tenth O site, O is bonded in a distorted water-like geometry to one Th and one N atom. In the eleventh O site, O is bonded in a bent 120 degrees geometry to one Th and one O atom. The O–O bond length is 1.24 Å. In the twelfth O site, O is bonded in a single-bond geometry to one N atom. In the thirteenth O site, O is bonded in a single-bond geometry to one O atom. In the fourteenth O site, O is bonded in a distorted water-like geometry to one Th and one N atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThV2TeO12 by Materials Project

ThV2TeO12 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. Th is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Th–O bond distances ranging from 2.31–2.63 Å. There are two inequivalent V sites. In the first V site, V is bonded in a 5-coordinate geometry to five O atoms. There are a spread of V–O bond distances ranging from 1.64–2.08 Å. In the second V site, V is bonded to four O atoms to form VO4 tetrahedra that share corners with two equivalent TeO6 octahedra. The corner-sharing octahedra tilt angles range from 48–50°. There are a spread of V–O bond distances ranging from 1.69–1.79 Å. Te is bonded to six O atoms to form TeO6 octahedra that share corners with two equivalent VO4 tetrahedra. There are a spread of Te–O bond distances ranging from 1.89–1.98 Å. There are twelve inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one V atom. In the second O site, O is bonded in a distorted water-like geometry to one Th, one V, and one Te atom. In the third O site, O is bonded in a bent 120 degrees geometry to one V and one Te atom. In the fourth O site, O is bonded in a distorted bent 120 degrees geometry to one Th and one V atom. In the fifth O site, O is bonded in a distorted bent 150 degrees geometry to one Th and one V atom. In the sixth O site, O is bonded in a bent 150 degrees geometry to one Th and one Te atom. In the seventh O site, O is bonded in a distorted trigonal planar geometry to one Th, one V, and one Te atom. In the eighth O site, O is bonded in a distorted bent 150 degrees geometry to one Th and one V atom. In the ninth O site, O is bonded in a single-bond geometry to one Th atom. In the tenth O site, O is bonded in a distorted trigonal planar geometry to one Th, one V, and one Te atom. In the eleventh O site, O is bonded in a distorted bent 120 degrees geometry to one V and one Te atom. In the twelfth O site, O is bonded in a single-bond geometry to one Th atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th2Zn17 by Materials Project

Th2Zn17 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Th sites. In the first Th site, Th is bonded in a 12-coordinate geometry to eighteen Zn atoms. There are a spread of Th–Zn bond distances ranging from 3.18–3.49 Å. In the second Th site, Th is bonded in a 8-coordinate geometry to twenty Zn atoms. There are a spread of Th–Zn bond distances ranging from 3.14–3.43 Å. There are four inequivalent Zn sites. In the first Zn site, Zn is bonded in a 2-coordinate geometry to one Th and thirteen Zn atoms. There are a spread of Zn–Zn bond distances ranging from 2.56–2.97 Å. In the second Zn site, Zn is bonded to two equivalent Th and ten Zn atoms to form ZnTh2Zn10 cuboctahedra that share corners with twenty-two ZnTh2Zn10 cuboctahedra, edges with ten ZnTh3Zn9 cuboctahedra, and faces with eighteen ZnTh2Zn10 cuboctahedra. There are four shorter (2.62 Å) and four longer (2.67 Å) Zn–Zn bond lengths. In the third Zn site, Zn is bonded to two Th and ten Zn atoms to form a mixture of distorted face, edge, and corner-sharing ZnTh2Zn10 cuboctahedra. There are a spread of Zn–Zn bond distances ranging from 2.62–2.76 Å. In the fourth Zn site, Zn is bonded to three Th and nine Zn atoms to form a mixture of distorted face, edge, and corner-sharing ZnTh3Zn9 cuboctahedra. Both Zn–Zn bond lengths are 2.56 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K4Th(S2O9)2 by Materials Project

K4Th(S2O9)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are five inequivalent K sites. In the first K site, K is bonded to six O atoms to form distorted KO6 pentagonal pyramids that share corners with two equivalent KO7 hexagonal pyramids and corners with five SO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.67–2.90 Å. In the second K site, K is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of K–O bond distances ranging from 2.76–3.16 Å. In the third K site, K is bonded in a 8-coordinate geometry to six O atoms. There are a spread of K–O bond distances ranging from 2.74–2.80 Å. In the fourth K site, K is bonded in a distorted q6 geometry to ten O atoms. There are a spread of K–O bond distances ranging from 2.85–3.11 Å. In the fifth K site, K is bonded to seven O atoms to form distorted KO7 hexagonal pyramids that share corners with two equivalent KO6 pentagonal pyramids, corners with five SO4 tetrahedra, and an edgeedge with one SO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.74–2.96 Å. Th is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Th–O bond distances ranging from 2.39–2.51 Å. There are four inequivalent S sites. In the first S site, S is bonded to four O atoms to form SO4 tetrahedra that share a cornercorner with one KO7 hexagonal pyramid and a cornercorner with one KO6 pentagonal pyramid. There are a spread of S–O bond distances ranging from 1.47–1.52 Å. In the second S site, S is bonded to four O atoms to form SO4 tetrahedra that share a cornercorner with one KO7 hexagonal pyramid and a cornercorner with one KO6 pentagonal pyramid. There are a spread of S–O bond distances ranging from 1.46–1.54 Å. In the third S site, S is bonded to four O atoms to form SO4 tetrahedra that share corners with two equivalent KO7 hexagonal pyramids and corners with two equivalent KO6 pentagonal pyramids. There are a spread of S–O bond distances ranging from 1.46–1.53 Å. In the fourth S site, S is bonded to four O atoms to form SO4 tetrahedra that share a cornercorner with one KO7 hexagonal pyramid, a cornercorner with one KO6 pentagonal pyramid, and an edgeedge with one KO7 hexagonal pyramid. There are a spread of S–O bond distances ranging from 1.47–1.56 Å. There are eighteen inequivalent O sites. In the first O site, O is bonded in a 1-coordinate geometry to one K, one Th, and one S atom. In the second O site, O is bonded in a distorted bent 150 degrees geometry to one Th and one S atom. In the third O site, O is bonded in a 1-coordinate geometry to two K and one S atom. In the fourth O site, O is bonded in a distorted single-bond geometry to two K and one S atom. In the fifth O site, O is bonded in a distorted single-bond geometry to one Th and one S atom. In the sixth O site, O is bonded in a 1-coordinate geometry to one K, one Th, and one S atom. In the seventh O site, O is bonded in a distorted single-bond geometry to three K and one S atom. In the eighth O site, O is bonded in a distorted single-bond geometry to two K and one S atom. In the ninth O site, O is bonded in a distorted single-bond geometry to three K and one S atom. In the tenth O site, O is bonded in a distorted single-bond geometry to two K and one S atom. In the eleventh O site, O is bonded in a distorted single-bond geometry to two K, one Th, and one S atom. In the twelfth O site, O is bonded in a distorted single-bond geometry to one K, one Th, and one S atom. In the thirteenth O site, O is bonded in a distorted bent 150 degrees geometry to one Th and one S atom. In the fourteenth O site, O is bonded in a distorted single-bond geometry to three K and one S atom. In the fifteenth O site, O is bonded in a distorted single-bond geometry to two K and one S atom. In the sixteenth O site, O is bonded in a distorted single-bond geometry to two K and one S atom. In the seventeenth O site, O is bonded in a bent 150 degrees geometry to one K and one Th atom. In the eighteenth O site, O is bonded in a bent 120 degrees geometry to one K and one Th atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThSc2(BRh)12 by Materials Project

ThSc2(RhB)12 crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. Th is bonded in a 12-coordinate geometry to twelve Rh and twelve B atoms. There are four shorter (3.00 Å) and eight longer (3.20 Å) Th–Rh bond lengths. There are a spread of Th–B bond distances ranging from 3.02–3.19 Å. There are three inequivalent Sc sites. In the first Sc site, Sc is bonded in a 12-coordinate geometry to twelve Rh and twelve B atoms. There are a spread of Sc–Rh bond distances ranging from 2.89–3.19 Å. There are a spread of Sc–B bond distances ranging from 3.00–3.17 Å. In the second Sc site, Sc is bonded in a 12-coordinate geometry to twelve Rh and twelve B atoms. There are four shorter (2.91 Å) and eight longer (3.16 Å) Sc–Rh bond lengths. There are eight shorter (3.02 Å) and four longer (3.16 Å) Sc–B bond lengths. In the third Sc site, Sc is bonded in a 12-coordinate geometry to twelve Rh and twelve B atoms. There are four shorter (2.92 Å) and eight longer (3.18 Å) Sc–Rh bond lengths. There are eight shorter (3.02 Å) and four longer (3.12 Å) Sc–B bond lengths. There are six inequivalent Rh sites. In the first Rh site, Rh is bonded in a 5-coordinate geometry to one Th, two equivalent Sc, and five B atoms. There are a spread of Rh–B bond distances ranging from 2.19–2.23 Å. In the second Rh site, Rh is bonded in a 5-coordinate geometry to three Sc and five B atoms. There are four shorter (2.20 Å) and one longer (2.23 Å) Rh–B bond lengths. In the third Rh site, Rh is bonded in a 5-coordinate geometry to two equivalent Th, one Sc, and five B atoms. There are a spread of Rh–B bond distances ranging from 2.21–2.32 Å. In the fourth Rh site, Rh is bonded in a 5-coordinate geometry to two equivalent Th, one Sc, and five B atoms. There are a spread of Rh–B bond distances ranging from 2.20–2.31 Å. In the fifth Rh site, Rh is bonded in a 5-coordinate geometry to one Th, two equivalent Sc, and five B atoms. There are a spread of Rh–B bond distances ranging from 2.21–2.24 Å. In the sixth Rh site, Rh is bonded in a 5-coordinate geometry to three Sc and five B atoms. There are a spread of Rh–B bond distances ranging from 2.20–2.22 Å. There are six inequivalent B sites. In the first B site, B is bonded in a 6-coordinate geometry to three Sc, five Rh, and one B atom. The B–B bond length is 1.81 Å. In the second B site, B is bonded in a 6-coordinate geometry to one Th, two equivalent Sc, five Rh, and one B atom. The B–B bond length is 1.80 Å. In the third B site, B is bonded in a 6-coordinate geometry to one Th, two equivalent Sc, five Rh, and one B atom. The B–B bond length is 1.81 Å. In the fourth B site, B is bonded in a 6-coordinate geometry to three Sc, five Rh, and one B atom. The B–B bond length is 1.81 Å. In the fifth B site, B is bonded in a 6-coordinate geometry to two equivalent Th, one Sc, five Rh, and one B atom. The B–B bond length is 1.78 Å. In the sixth B site, B is bonded in a 6-coordinate geometry to two equivalent Th, one Sc, five Rh, and one B atom. The B–B bond length is 1.78 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThNi(N3O13)2 by Materials Project

Th(NO3)6NiO6O2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four water molecules, two NiO6 clusters, and two Th(NO3)6 clusters. In each NiO6 cluster, Ni is bonded in an octahedral geometry to six O atoms. There are a spread of Ni–O bond distances ranging from 1.82–1.86 Å. There are three inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Ni atom. In the second O site, O is bonded in a single-bond geometry to one Ni atom. In the third O site, O is bonded in a single-bond geometry to one Ni atom. In each Th(NO3)6 cluster, Th is bonded in a cuboctahedral geometry to twelve O atoms. There are a spread of Th–O bond distances ranging from 2.54–2.65 Å. There are three inequivalent N sites. In the first N site, N is bonded in a trigonal planar geometry to three O atoms. There are a spread of N–O bond distances ranging from 1.25–1.28 Å. In the second N site, N is bonded in a trigonal planar geometry to three O atoms. There are a spread of N–O bond distances ranging from 1.22–1.30 Å. In the third N site, N is bonded in a trigonal planar geometry to three O atoms. There are a spread of N–O bond distances ranging from 1.26–1.28 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the second O site, O is bonded in a single-bond geometry to one N atom. In the third O site, O is bonded in a single-bond geometry to one N atom. In the fourth O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the fifth O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the sixth O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the seventh O site, O is bonded in a single-bond geometry to one N atom. In the eighth O site, O is bonded in a distorted water-like geometry to one Th and one N atom. In the ninth O site, O is bonded in a distorted single-bond geometry to one Th and one N atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThZn(N3O13)2 by Materials Project

Th(NO3)6ZnO6O2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four water molecules, two Th(NO3)6 clusters, and two zinc;hexahydrate molecules. In each Th(NO3)6 cluster, Th is bonded in a cuboctahedral geometry to twelve O atoms. There are a spread of Th–O bond distances ranging from 2.54–2.64 Å. There are three inequivalent N sites. In the first N site, N is bonded in a trigonal planar geometry to three O atoms. There are a spread of N–O bond distances ranging from 1.25–1.28 Å. In the second N site, N is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.22 Å) and two longer (1.29 Å) N–O bond length. In the third N site, N is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.25 Å) and two longer (1.27 Å) N–O bond length. There are nine inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the second O site, O is bonded in a single-bond geometry to one N atom. In the third O site, O is bonded in a single-bond geometry to one N atom. In the fourth O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the fifth O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the sixth O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the seventh O site, O is bonded in a single-bond geometry to one N atom. In the eighth O site, O is bonded in a distorted water-like geometry to one Th and one N atom. In the ninth O site, O is bonded in a distorted single-bond geometry to one Th and one N atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th2SiGe by Materials Project

Th2GeSi crystallizes in the orthorhombic Pmc2_1 space group. The structure is three-dimensional. there are two inequivalent Th sites. In the first Th site, Th is bonded in a 7-coordinate geometry to three equivalent Ge and four equivalent Si atoms. There are a spread of Th–Ge bond distances ranging from 3.12–3.28 Å. There are two shorter (3.05 Å) and two longer (3.09 Å) Th–Si bond lengths. In the second Th site, Th is bonded in a 7-coordinate geometry to four equivalent Ge and three equivalent Si atoms. There are two shorter (3.07 Å) and two longer (3.09 Å) Th–Ge bond lengths. There are a spread of Th–Si bond distances ranging from 3.07–3.30 Å. Ge is bonded in a 9-coordinate geometry to seven Th and two equivalent Si atoms. Both Ge–Si bond lengths are 2.80 Å. Si is bonded in a 9-coordinate geometry to seven Th and two equivalent Ge atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Impact of Noncovalent Interactions on the Structural Chemistry of Thorium(IV)-Aquo-Chloro Complexes

Five novel tetravalent thorium (Th) compounds that consist of Th(H 2 O) x Cl y structural units were isolated from acidic aqueous solutions using a series of nitrogen-containing heterocyclic hydrogen (H) bond donors. Taken together with three previously reported phases, the compounds provide a series of monomeric Th IV complexes wherein the effects of noncovalent interactions (and H-bond donor identity) on Th structural chemistry can be examined. Seven distinct structural units of the general formulas [Th(H 2 O) x Cl 8–x ] x-4 (x = 2, 4) and [Th(H 2 O) x Cl 9–x] x-5 (x = 5–7) are described. The complexes range from chloride-deficient [Th(H 2 O) 7 Cl 2 ] 2+ to chloride-rich [Th(H 2 O) 2 Cl 6 ] 2– species, and theory was used to understand the relative energies that separate complexes within this series via the stepwise chloride addition to an aquated Th cation. Electronic structure theory predicted the reaction energies of chloride addition and release of water through a series of transformations, generally highlighting an energetic driving force for chloride complexation. To probe the role of the counterion in the stabilization of these complexes, electrostatic potential (ESP) surfaces were calculated. Finally, the ESP surfaces indicated a dependence of the chloride distribution about the Th metal center on the pK a of the countercation, highlighting the directing effects of noncovalent interactions (e.g., Hbonding) on Th speciation.

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

Confident detection of doubly ionized thorium in the extreme Ap star CPD-62° 2717

Despite the Universe containing primordial thorium (Th) of sufficient abundance to appear in stellar spectra, detection of Th has to date been tentative and based on just a few weak and blended lines. Here, we present convincing evidence not only for the first Th detection in a magnetic chemically peculiar Ap star but also for the first detection of Th iii in a stellar spectrum. CPD-62° 2717 was initially recognized as a highly magnetized Ap star due to resolved magnetically split lines captured in H-band spectra from the SDSS/APOGEE survey. The star was subsequently pinpointed as extraordinarily peculiar when careful inspection of the H-band line content revealed the presence of five lines of Th iii, none of which are detected in the other ∼1500 APOGEE-observed Ap stars. Follow-up with the VLT + UVES confirmed a similarly peculiar optical spectrum featuring dozens of Th iii lines, among other peculiarities. Unlike past claims of Th detection, and owing to high-resolution observations of the strong (∼8–12 kG) magnetic field of CPD-62° 2717, the detection of Th iii can in this case be supported by matches between the observed and theoretical magnetic splitting patterns. Comparison of CPD-62° 2717 to stars for which Th overabundances have been previously reported (e.g. Przybylski’s Star) indicates that only for CPD-62° 2717 is the Th detection certain. Along with the focus on Th iii, we use time series measurements of the magnetic field modulus to constrain the rotation period of CPD-62° 2717 to ∼4.8 yr, thus establishing it as a new example of a superslowly rotating Ap star.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2024

First-principles determination of the phonon-point defect scattering and thermal transport due to fission products in ThO 2

This work presents the first-principles calculations of the lattice thermal conductivity degradation due to point defects in thorium dioxide using an iterative solution of the Pierels-Boltzmann transport equation. We have used the non perturbative Green’s function methodology to compute the phonon- point defect scattering rates that consider the local distortion around the point defect, including the mass difference changes, interatomic force constants, and structural relaxation near the point defects. The point defects considered in this work include the vacancy of thorium ($V$ $TH$ ) and oxygen ($V$ $O$ ), substitutions of helium ($He$ $Th$ ), krypton ($Kr$ $Th$ ), zirconium ($Zr$ $Th$ ), iodine ($I$ $Th$ ) and xenon ($Xe$ $Th$ ) in the thorium site, and the three different configurations of the Schottky defects. The results of the phonon-defect scattering rate reveal that, among all the considered intrinsic defects, the thorium vacancy and helium substitution in the thorium site scatter the phonon most due to the substantial changes in the force constant and structural distortions. The scattering of phonons due to the substitutional defects unveils that the zirconium atom scatters phonons the least, followed by xenon, iodine, krypton, and helium. This is contrary to the intuition that the scattering strength follows $He$ $Th$ > $Kr$ $Th$ > $Zr$ $Th$ > $I$ $Th$ > $Xe$ $Th$ based on the mass difference. This striking difference in the zirconium phonon scattering is due to the local chemical environment changes. Zirconium is an electropositive element with valency similar to thorium and, therefore, can bond with the oxygen atoms, thus creating less force constant variance compared to iodine, an electronegative element noble gas helium, xenon, and krypton. In conclusion, these results can serve as the benchmark for the analytical models and help the engineering-scale modeling effort for nuclear design.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th2S3 by Materials Project

Th2S3 is Stibnite structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Th sites. In the first Th site, Th is bonded in a 7-coordinate geometry to eight S atoms. There are a spread of Th–S bond distances ranging from 2.87–3.48 Å. In the second Th site, Th is bonded to seven S atoms to form a mixture of distorted edge and corner-sharing ThS7 pentagonal bipyramids. There are a spread of Th–S bond distances ranging from 2.85–2.90 Å. There are three inequivalent S sites. In the first S site, S is bonded to five Th atoms to form a mixture of edge and corner-sharing STh5 square pyramids. In the second S site, S is bonded to five Th atoms to form a mixture of distorted edge and corner-sharing STh5 trigonal bipyramids. In the third S site, S is bonded in a distorted rectangular see-saw-like geometry to five Th atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThFe5P3 by Materials Project

ThFe5P3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Th is bonded in a 8-coordinate geometry to ten Fe and six P atoms. There are a spread of Th–Fe bond distances ranging from 2.96–3.17 Å. There are a spread of Th–P bond distances ranging from 2.88–2.95 Å. There are five inequivalent Fe sites. In the first Fe site, Fe is bonded to three equivalent Th and four P atoms to form a mixture of distorted edge, corner, and face-sharing FeTh3P4 tetrahedra. There are a spread of Fe–P bond distances ranging from 2.31–2.35 Å. In the second Fe site, Fe is bonded in a 1-coordinate geometry to five P atoms. There are a spread of Fe–P bond distances ranging from 2.23–2.57 Å. In the third Fe site, Fe is bonded to three equivalent Th and four P atoms to form a mixture of distorted edge, corner, and face-sharing FeTh3P4 tetrahedra. There are a spread of Fe–P bond distances ranging from 2.31–2.40 Å. In the fourth Fe site, Fe is bonded to three equivalent Th and four P atoms to form a mixture of distorted edge, corner, and face-sharing FeTh3P4 tetrahedra. There are a spread of Fe–P bond distances ranging from 2.23–2.37 Å. In the fifth Fe site, Fe is bonded to one Th and four P atoms to form a mixture of distorted edge, corner, and face-sharing FeThP4 tetrahedra. There are a spread of Fe–P bond distances ranging from 2.14–2.25 Å. There are three inequivalent P sites. In the first P site, P is bonded in a 9-coordinate geometry to two equivalent Th and seven Fe atoms. In the second P site, P is bonded in a 9-coordinate geometry to two equivalent Th and seven Fe atoms. In the third P site, P is bonded in a 9-coordinate geometry to two equivalent Th and seven Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThFe3 by Materials Project

ThFe3 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Th sites. In the first Th site, Th is bonded in a 12-coordinate geometry to twelve Fe atoms. There are a spread of Th–Fe bond distances ranging from 2.98–3.15 Å. In the second Th site, Th is bonded in a 6-coordinate geometry to eighteen Fe atoms. There are six shorter (2.97 Å) and twelve longer (3.28 Å) Th–Fe bond lengths. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to five Th and seven Fe atoms to form a mixture of face, edge, and corner-sharing FeTh5Fe7 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.50–2.59 Å. In the second Fe site, Fe is bonded in a 12-coordinate geometry to three equivalent Th and six equivalent Fe atoms. In the third Fe site, Fe is bonded to six equivalent Th and six equivalent Fe atoms to form FeTh6Fe6 cuboctahedra that share corners with twelve equivalent FeTh5Fe7 cuboctahedra, edges with six equivalent FeTh6Fe6 cuboctahedra, and faces with eighteen equivalent FeTh5Fe7 cuboctahedra.

36 MATERIALS SCIENCE↗