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DOE OSTI2020

Materials Data on Ce(Al5Fe)2 by Materials Project

Al10Fe2Ce crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Ce is bonded in a 8-coordinate geometry to four equivalent Fe and sixteen Al atoms. All Ce–Fe bond lengths are 3.41 Å. There are a spread of Ce–Al bond distances ranging from 3.12–3.62 Å. Fe is bonded in a 10-coordinate geometry to two equivalent Ce and ten Al atoms. There are a spread of Fe–Al bond distances ranging from 2.52–2.71 Å. There are five inequivalent Al sites. In the first Al site, Al is bonded in a 2-coordinate geometry to two equivalent Ce, two equivalent Fe, and eight Al atoms. There are a spread of Al–Al bond distances ranging from 2.61–2.82 Å. In the second Al site, Al is bonded in a 12-coordinate geometry to one Ce, two equivalent Fe, and nine Al atoms. There are a spread of Al–Al bond distances ranging from 2.67–3.02 Å. In the third Al site, Al is bonded in a 2-coordinate geometry to two equivalent Ce, two equivalent Fe, and eight Al atoms. There are a spread of Al–Al bond distances ranging from 2.57–2.75 Å. In the fourth Al site, Al is bonded in a 2-coordinate geometry to one Ce, two equivalent Fe, and eight Al atoms. There are one shorter (2.70 Å) and two longer (2.78 Å) Al–Al bond lengths. In the fifth Al site, Al is bonded in a 2-coordinate geometry to two equivalent Ce, two equivalent Fe, and eight Al atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Ce IV 70 Oxosulfate Rings, Frameworks, Supramolecular Assembly, and Redox Activity**

Abstract M IV molecular oxo‐clusters (M=Zr, Hf, Ce, Th, U, Np, Pu) are prolific in bottoms‐up material design, catalysis, and elucidating reaction pathways in nature and in synthesis. Here we introduce Ce 70 , a wheel‐shaped oxo‐cluster, [Ce IV 70 (OH) 36 (O) 64 (SO 4 ) 60 (H 2 O) 10 ] 4− . Ce 70 crystallizes into intricate high pore volume frameworks with divalent transition metals and Ce‐monomer linkers. Eight crystal‐structures feature four framework types in which the Ce 70 ‐rings are linked as propellers, in offset‐stacks, in a tartan pattern, and as isolated rings. Small‐angle X‐ray scattering of Ce 70 dissolved in butylamine, with and without added cations (Ce IV , alkaline earths, Mn II ), shows the metals‘ differentiating roles in ring linking, leading to supramolecular assemblies. The large acidic pores and abundant terminal sulfates provide ion‐exchange behavior, demonstrated with U IV and Nd III . Frameworks featuring Ce III/IV ‐monomer linkers demonstrate both oxidation and reduction. This study opens the door to mixed‐metal, highly porous framework catalysts, and new clusters for metal‐organic framework design

Colliard, Ian↗
DOE OSTI2021

Ce IV 70 oxosulfate rings, frameworks, supramolecular assembly and redox activity

M IV molecular oxo-clusters (M=Zr, Hf, Ce, Th, U, Np, Pu) are prolific in bottoms-up material design, catalysis, and elucidating reaction pathways in nature and in synthesis. Here we introduce Ce 70 , a wheel-shaped oxo-cluster, [Ce IV 70 -(OH) 36 (O) 64 (SO 4 ) 60 (H 2 O) 10 ] 4- . Ce 70 crystallizes into intricate high pore volume frameworks with divalent transition metals and Ce-monomer linkers. Eight crystal-structures feature four framework types in which the Ce 70 -rings are linked as propellers, in offset-stacks, in a tartan pattern, and as isolated rings. In this work, small-angle X-ray scattering of Ce 70 dissolved in butylamine, with and without added cations (Ce IV , alkaline earths, Mn II ), shows the metals‘ differentiating roles in ring linking, leading to supramolecular assemblies. The large acidic pores and abundant terminal sulfates provide ion-exchange behavior, demonstrated with U IV and Nd III . Frameworks featuring Ce III/IV -monomer linkers demonstrate both oxidation and reduction. Furthermore, this study opens the door to mixed-metal, highly porous framework catalysts, and new clusters for metal-organic framework design.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Hypereutectic Al-Ce-X (X=Mn, Cr, V, Mo, W) alloys fabricated by laser powder-bed fusion

Here, we characterize the microstructures and high-temperature mechanical properties of Al-2Ce and ternary Al-2Ce-1X (at.%) alloys fabricated by laser powder-bed fusion (LPBF), where X = Mn, Cr, V, Mo, and W are slow-diffusing transition metals. All ternary alloys show a hypereutectic microstructure in the as-LPBF state, containing an interconnected network of eutectic Al 11 Ce 3 phases (~10 vol.%) and an additional population of submicron, equiaxed Al 20 CeX 2 primary precipitates (~10 vol.%) which are isomorphous among these five alloys. Similar microstructures are present in arc-melted rods and atomized powders but are coarser due to the slower cooling rates in these processes. The hardness of the as-LPBF ternary Al-Ce-X alloys (1300–1400 MPa) is higher than that of the binary Al-Ce alloy (~1100 MPa) due to the higher volume fraction of strengthening phases. Furthermore, during exposure at 400 °C for up to three months, greater hardness retention is achieved in the ternary Al-Ce-X alloys (65–75%) than in the binary Al-Ce alloy (~55%), which is attributed to the extreme coarsening resistance of the Al 20 CeX 2 precipitates imparted by the very slow-diffusing ternary solute. These coarsening-resistant Al 20 CeX 2 precipitates also substantially improve alloy creep resistance, increasing the threshold stress for dislocation creep at 300°C from ~32 MPa for the binary Al-Ce alloy to ~77–100 MPa for the ternary Al-Ce-X alloys, and at 400°C from <10 MPa for the binary Al-Ce alloy to >40 MPa for the ternary Al-Ce-V alloy.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Phase stability in cast and additively manufactured Al-rich Al-Cu-Ce alloys

Additively manufactured (AM) eutectic Al alloy systems have been studied extensively for advantageous thermal stability and mechanical properties due to their refined microstructures. Al-Cu-Ce alloys are one subset of these AM eutectic alloys. Here we studied phase stability in AM Al-Cu-Ce alloys and compared it to that of conventionally cast ones. A new phase, Al 8 Cu 3 Ce, was identified in the microstructures of both AM and cast Al-Cu-Ce alloys. This Al 8 Cu 3 Ce phase was not previously included on experimental or thermodynamically calculated phase diagrams of the Al-Cu-Ce system. Therefore, we performed additional thermodynamic modeling of the system. These models were experimentally validated with cast and subsequently heat-treated Al-Cu-Ce alloys. We found that despite the refined microstructure of the AM alloys, the phases formed were consistent with the cast alloys, suggesting that AM processing did not significantly alter the formation and stability of phases from that in the conventional alloys. In conclusion, this work has resolved inconsistent previous descriptions of the Al-Cu-Ce ternary phase diagram in the Al-rich region and resulted in the addition of the Al 8 Cu 3 Ce as an equilibrium phase above 500 °C.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Thallium-based scintillators for high-resolution gamma-ray spectroscopy: Ce 3+ - doped Tl 2 LaCl 5 and Tl 2 LaBr 5

In this paper we report on the crystallographic and scintillation properties of Tl 2 LaCl 5 :Ce 3 + and Tl 2 LaBr 5 :Ce 3 + , two novel thallium-containing high-resolution scintillators for gamma-ray spectroscopy. Crystals of Tl 2 LaCl 5 :Ce 3 + and Tl 2 LaBr 5 :Ce 3 + were grown by the Vertical Bridgman method up to 1-inch diameter and 1-inch long. Single crystals of Tl 2 LaCl 5 :Ce 3 + and Tl 2 LaBr 5 :Ce 3 + belong to the orthorhombic system with space group 62 and have a density of 5.16 and 5.98 g/cm 3 , respectively. The scintillators show high light yields of up to 68,000 photons/MeV, excellent gamma-ray energy resolution of ≤ 3% at 662 keV, a fast scintillation decay, and a proportional response over a wide range of energies from 32 keV up to 1275 keV. Density Functional Theory calculations show that the Ce 3 + energy levels are inside the bandgap despite the smaller bandgap of Tl 2 LaCl 5 and Tl 2 LaBr 5 compared to K 2 LaCl 5 and K 2 LaBr 5 . Finally, a systematic Ce 3 + concentration study was performed for Tl 2 LaCl 5 :Ce 3 + and trends observed.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2020

Materials Data on Ce(GePt)2 by Materials Project

Ce(PtGe)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ce is bonded in a 12-coordinate geometry to eight Pt and eight Ge atoms. There are four shorter (3.34 Å) and four longer (3.35 Å) Ce–Pt bond lengths. There are four shorter (3.30 Å) and four longer (3.35 Å) Ce–Ge bond lengths. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded in a 4-coordinate geometry to four equivalent Ce and four equivalent Ge atoms. All Pt–Ge bond lengths are 2.55 Å. In the second Pt site, Pt is bonded in a 5-coordinate geometry to four equivalent Ce and five Ge atoms. There are one shorter (2.46 Å) and four longer (2.52 Å) Pt–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 4-coordinate geometry to four equivalent Ce and four equivalent Pt atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent Ce and five Pt atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce(SnIr)2 by Materials Project

Ce(IrSn)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ce is bonded in a 12-coordinate geometry to eight Ir and eight Sn atoms. There are four shorter (3.40 Å) and four longer (3.50 Å) Ce–Ir bond lengths. There are four shorter (3.38 Å) and four longer (3.56 Å) Ce–Sn bond lengths. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 9-coordinate geometry to four equivalent Ce and five Sn atoms. There are one shorter (2.59 Å) and four longer (2.66 Å) Ir–Sn bond lengths. In the second Ir site, Ir is bonded to four equivalent Ce and four equivalent Sn atoms to form distorted IrCe4Sn4 tetrahedra that share corners with twelve equivalent SnCe4Ir4 tetrahedra, edges with two equivalent SnCe4Ir4 tetrahedra, edges with four equivalent IrCe4Sn4 tetrahedra, and faces with four equivalent IrCe4Sn4 tetrahedra. All Ir–Sn bond lengths are 2.64 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 9-coordinate geometry to four equivalent Ce and five Ir atoms. In the second Sn site, Sn is bonded to four equivalent Ce and four equivalent Ir atoms to form distorted SnCe4Ir4 tetrahedra that share corners with twelve equivalent IrCe4Sn4 tetrahedra, edges with two equivalent IrCe4Sn4 tetrahedra, edges with four equivalent SnCe4Ir4 tetrahedra, and faces with four equivalent SnCe4Ir4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce(PRh)2 by Materials Project

Ce(RhP)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ce is bonded in a 12-coordinate geometry to eight Rh and eight P atoms. There are four shorter (3.19 Å) and four longer (3.21 Å) Ce–Rh bond lengths. There are four shorter (3.12 Å) and four longer (3.15 Å) Ce–P bond lengths. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 9-coordinate geometry to four equivalent Ce and five P atoms. There are four shorter (2.35 Å) and one longer (2.36 Å) Rh–P bond lengths. In the second Rh site, Rh is bonded in a 12-coordinate geometry to four equivalent Ce and four equivalent P atoms. All Rh–P bond lengths are 2.47 Å. There are two inequivalent P sites. In the first P site, P is bonded in a 8-coordinate geometry to four equivalent Ce and four equivalent Rh atoms. In the second P site, P is bonded in a 9-coordinate geometry to four equivalent Ce and five Rh atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce(ClO)3 by Materials Project

Ce(OCl)3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ce is bonded in a 1-coordinate geometry to three O and five Cl atoms. There are one shorter (2.04 Å) and two longer (2.38 Å) Ce–O bond lengths. There are a spread of Ce–Cl bond distances ranging from 2.79–2.98 Å. There are two inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Ce atom. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one Ce and one Cl atom. The O–Cl bond length is 2.32 Å. There are two inequivalent Cl sites. In the first Cl site, Cl is bonded in a distorted trigonal planar geometry to one Ce and two equivalent O atoms. In the second Cl site, Cl is bonded in a water-like geometry to two equivalent Ce atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce(AsRh)2 by Materials Project

Ce(RhAs)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ce is bonded in a 12-coordinate geometry to eight Rh and eight As atoms. There are four shorter (3.30 Å) and four longer (3.32 Å) Ce–Rh bond lengths. There are four shorter (3.25 Å) and four longer (3.29 Å) Ce–As bond lengths. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 12-coordinate geometry to four equivalent Ce and four equivalent As atoms. All Rh–As bond lengths are 2.56 Å. In the second Rh site, Rh is bonded in a 9-coordinate geometry to four equivalent Ce and five As atoms. There are one shorter (2.42 Å) and four longer (2.47 Å) Rh–As bond lengths. There are two inequivalent As sites. In the first As site, As is bonded in a 8-coordinate geometry to four equivalent Ce and four equivalent Rh atoms. In the second As site, As is bonded in a 9-coordinate geometry to four equivalent Ce and five Rh atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce(AlAu)2 by Materials Project

Ce(AuAl)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ce is bonded in a 8-coordinate geometry to eight Au and eight Al atoms. There are four shorter (3.38 Å) and four longer (3.42 Å) Ce–Au bond lengths. There are four shorter (3.39 Å) and four longer (3.43 Å) Ce–Al bond lengths. There are two inequivalent Au sites. In the first Au site, Au is bonded to four equivalent Ce and four equivalent Al atoms to form distorted AuCe4Al4 tetrahedra that share corners with twelve equivalent AlCe4Au4 tetrahedra, edges with two equivalent AlCe4Au4 tetrahedra, edges with four equivalent AuCe4Al4 tetrahedra, and faces with four equivalent AuCe4Al4 tetrahedra. All Au–Al bond lengths are 2.59 Å. In the second Au site, Au is bonded in a 5-coordinate geometry to four equivalent Ce and five Al atoms. There are one shorter (2.51 Å) and four longer (2.61 Å) Au–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded to four equivalent Ce and four equivalent Au atoms to form distorted AlCe4Au4 tetrahedra that share corners with twelve equivalent AuCe4Al4 tetrahedra, edges with two equivalent AuCe4Al4 tetrahedra, edges with four equivalent AlCe4Au4 tetrahedra, and faces with four equivalent AlCe4Au4 tetrahedra. In the second Al site, Al is bonded in a 5-coordinate geometry to four equivalent Ce and five Au atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce(SnPd)2 by Materials Project

Ce(PdSn)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ce is bonded in a 12-coordinate geometry to eight Pd and eight Sn atoms. There are four shorter (3.46 Å) and four longer (3.54 Å) Ce–Pd bond lengths. There are four shorter (3.49 Å) and four longer (3.56 Å) Ce–Sn bond lengths. There are two inequivalent Pd sites. In the first Pd site, Pd is bonded in a 4-coordinate geometry to four equivalent Ce and four equivalent Sn atoms. All Pd–Sn bond lengths are 2.67 Å. In the second Pd site, Pd is bonded in a 9-coordinate geometry to four equivalent Ce and five Sn atoms. There are one shorter (2.60 Å) and four longer (2.68 Å) Pd–Sn bond lengths. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 4-coordinate geometry to four equivalent Ce and four equivalent Pd atoms. In the second Sn site, Sn is bonded in a 9-coordinate geometry to four equivalent Ce and five Pd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce(SbPd)2 by Materials Project

Ce(PdSb)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ce is bonded in a 12-coordinate geometry to eight Pd and eight Sb atoms. There are four shorter (3.44 Å) and four longer (3.59 Å) Ce–Pd bond lengths. There are four shorter (3.51 Å) and four longer (3.58 Å) Ce–Sb bond lengths. There are two inequivalent Pd sites. In the first Pd site, Pd is bonded in a 8-coordinate geometry to four equivalent Ce and four equivalent Sb atoms. All Pd–Sb bond lengths are 2.70 Å. In the second Pd site, Pd is bonded in a 9-coordinate geometry to four equivalent Ce and five Sb atoms. There are one shorter (2.58 Å) and four longer (2.68 Å) Pd–Sb bond lengths. There are two inequivalent Sb sites. In the first Sb site, Sb is bonded in a 4-coordinate geometry to four equivalent Ce and four equivalent Pd atoms. In the second Sb site, Sb is bonded in a 9-coordinate geometry to four equivalent Ce and five Pd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce(SnRh)2 by Materials Project

Ce(RhSn)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ce is bonded in a 12-coordinate geometry to eight Rh and eight Sn atoms. There are four shorter (3.45 Å) and four longer (3.48 Å) Ce–Rh bond lengths. There are four shorter (3.44 Å) and four longer (3.53 Å) Ce–Sn bond lengths. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 4-coordinate geometry to four equivalent Ce and four equivalent Sn atoms. All Rh–Sn bond lengths are 2.64 Å. In the second Rh site, Rh is bonded in a 9-coordinate geometry to four equivalent Ce and five Sn atoms. There are one shorter (2.57 Å) and four longer (2.67 Å) Rh–Sn bond lengths. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded to four equivalent Ce and four equivalent Rh atoms to form a mixture of distorted face and edge-sharing SnCe4Rh4 tetrahedra. In the second Sn site, Sn is bonded in a 9-coordinate geometry to four equivalent Ce and five Rh atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce(GaPd)2 by Materials Project

Ce(PdGa)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ce is bonded in a 4-coordinate geometry to eight Pd and eight Ga atoms. There are four shorter (3.27 Å) and four longer (3.41 Å) Ce–Pd bond lengths. There are four shorter (3.32 Å) and four longer (3.34 Å) Ce–Ga bond lengths. There are two inequivalent Pd sites. In the first Pd site, Pd is bonded to four equivalent Ce and four equivalent Ga atoms to form distorted PdCe4Ga4 tetrahedra that share corners with twelve equivalent GaCe4Pd4 tetrahedra, edges with two equivalent GaCe4Pd4 tetrahedra, edges with four equivalent PdCe4Ga4 tetrahedra, and faces with four equivalent PdCe4Ga4 tetrahedra. All Pd–Ga bond lengths are 2.54 Å. In the second Pd site, Pd is bonded in a 9-coordinate geometry to four equivalent Ce and five Ga atoms. There are one shorter (2.49 Å) and four longer (2.55 Å) Pd–Ga bond lengths. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded to four equivalent Ce and four equivalent Pd atoms to form distorted GaCe4Pd4 tetrahedra that share corners with twelve equivalent PdCe4Ga4 tetrahedra, edges with two equivalent PdCe4Ga4 tetrahedra, edges with four equivalent GaCe4Pd4 tetrahedra, and faces with four equivalent GaCe4Pd4 tetrahedra. In the second Ga site, Ga is bonded in a 9-coordinate geometry to four equivalent Ce and five Pd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce(ZnAu2)2 by Materials Project

Ce(Au2Zn)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ce is bonded to twelve Au atoms to form a mixture of distorted edge and face-sharing CeAu12 cuboctahedra. There are four shorter (3.02 Å) and eight longer (3.35 Å) Ce–Au bond lengths. There are five inequivalent Au sites. In the first Au site, Au is bonded in a 11-coordinate geometry to three equivalent Ce, four Au, and four equivalent Zn atoms. There are two shorter (2.80 Å) and two longer (2.89 Å) Au–Au bond lengths. All Au–Zn bond lengths are 2.89 Å. In the second Au site, Au is bonded in a 11-coordinate geometry to three equivalent Ce, four Au, and four equivalent Zn atoms. There are two shorter (2.80 Å) and two longer (2.89 Å) Au–Au bond lengths. All Au–Zn bond lengths are 2.89 Å. In the third Au site, Au is bonded in a 11-coordinate geometry to three equivalent Ce, four Au, and four equivalent Zn atoms. Both Au–Au bond lengths are 2.89 Å. All Au–Zn bond lengths are 2.89 Å. In the fourth Au site, Au is bonded in a 11-coordinate geometry to three equivalent Ce, four Au, and four equivalent Zn atoms. Both Au–Au bond lengths are 2.80 Å. All Au–Zn bond lengths are 2.89 Å. In the fifth Au site, Au is bonded in a 11-coordinate geometry to three equivalent Ce, four Au, and four equivalent Zn atoms. The Au–Au bond length is 2.80 Å. All Au–Zn bond lengths are 2.89 Å. Zn is bonded in a 10-coordinate geometry to eight Au and two equivalent Zn atoms. Both Zn–Zn bond lengths are 2.70 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Trapping an Unexpected/Unprecedented Hexanuclear Ce(III) Hydrolysis Product with Neutral 4‐Amino‐1,2,4‐triazole

Using Ce(III) as both a representative lanthanide and actinide analog, the ability of mixtures of acidic and basic azoles to allow direct access to homoleptic N-donor f-element complexes in one pot reactions from hydrated salts as starting materials was examined by reacting mixtures of 4-amino-1,2,4-triazole (4-NH 2 -1,2,4-Triaz), 5-amino-tetrazole (5-NH 2 -HTetaz), and 1,2,3-triazole (1,2,3-HTriaz) in 1 : 1 and 1 : 3 ratios with CeCl 3 ⋅ 7H 2 O, [C 2 mim] 3 [CeCl 6 ] ([C 2 mim] + =1-ethyl-2-methylimidazolium), and Ce(NO 3 ) 3 ⋅ 6H 2 O. Although unsuccessful in our goal, structural analysis revealed that neutral 4-NH 2 -1,2,4-Triaz is structure directing via η 2 μ 2 κ 2 bridging, with the formation of the dinuclear complexes [Ce 2 Cl 2 (μ 2 -4-NH 2 -1,2,4-Triaz) 4 (H 2 O) 8 ]Cl 4 ⋅ 4H 2 O, [Ce 2 (μ 2 -4-NH 2 -1,2,4-Triaz) 4 (4-NH 2 -1,2,4-Triaz) 2 (Cl) 6 ], and [4-NH 2 -1,2,4-HTriaz][Ce 2 (μ 2 -4-NH 2 -1,2,4-Triaz) 2 (μ 2 -NO 3 )(NO 3 ) 6 (H 2 O) 2 ]. When the synthetic conditions favored hydrolysis, the hexanuclear Ce(III) complex [Ce 6 (μ 3 -O) 4 (μ 3 -OH) 2 (μ 3 -Cl) 2 (Cl) 6 (μ 2 -4-NH 2 -1,2,4-Triaz) 12 ] ⋅ 7H 2 O was isolated. This unexpected hydrolysis product represents the first example of a high nuclearity lanthanide complex where all Ln atoms are pairwise connected through 12 N-donor ligands or 12 neutral bridging ligands of any type, a rare example of incorporation of non-oxo coordinating anions in the M 6 X 8 core, and the first reported Ce(III) hexanuclear complex of this type.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗