Crystallization at the solid-liquid interface is difficult to spectroscopically observe and therefore challenging to understand and ultimately control at the molecular level. The Ce70-torroid formulated [Ce IV 70(OH)36(O)64(SO4)60(H2O)10] 4-, part of a larger emerging family of M IV 70materials (M=Zr, U, Ce), presents such an opportunity. We have elucidated assembly mechanisms by X-ray scattering (small-angle scattering and total scattering) of solutions and solids, as well as crystallizing and identifying fragments of Ce70 by single-crystal X-ray diffraction. Fragments show evidence for templated growth (Ce5, [Ce5(O)3(SO4)12] 10-) and modular assembly from hexamer (Ce6) building units (Ce13, [Ce13(OH)6(O)12(SO4)14(Η2Ο)14] 6and Ce62, [Ce62(OH)30(O)58(SO4)58] 14-). Ce62, an almost complete ring, precipitates instantaneously in the presence of ammonium cations as two torqued arcs that interlock by hydrogen boding through NH4 + , which can also be replaced by other cations, demonstrated with Ce III . Room temperature rapid assembly of both Ce70 and Ce62, respectively, by addition of Li + and NH4 + , along with ionexchange and redox behavior, invite exploitation of this emerging material family in environmental and energy applications. Ce70, [Ce IV 70(OH)36(O)64(SO4)60] 4-, was described prior, and is also isostructural with Zr70 and U70. [49][50][51][52] Briefly, the Ce70 cluster can be viewed as ten Ce6-hexamers that alternate with ten Ce1-monomers. Four sulfates bridge each Ce6 and Ce1 along the outer rim, and four additional sulfates bridge only Ce6 units along the inner rim. Each fragment discussed later can be viewed in the same context. The Ce62, [Ce62(OH)30(O)58(SO4)58] 14-, consisting of ~90% of the ring, contains nine Ce6 and eight Ce1. Ce13, [Ce13(OH)6(O)12(SO4)14(Η2Ο)14] 6-, consists of two Ce6 and Ce1, and is approximately 20% of the ring. Ce5 [Ce5(O)3(SO4)12] 10-, resembles half of the Ce6 plus two flanking monomers. These clusters and their intrinsic relation to the Ce70, summarized in figure 1, serve as crystallographic snapshots of mechanistic pathways for ring formation.

Crystallization at the solid-liquid interface is difficult to spectroscopically observe and therefore challenging to understand and ultimately control at the molecular level. The Ce70-torroid formulated [CeIV70(OH)36(O)64(SO4)60(H2O)10] 4- , part of a larger emerging family of MIV70- materials (M=Zr, U, Ce), presents such an opportunity. We have elucidated assembly mechanisms by X-ray scattering (small-angle scattering and total scattering) of solutions and solids, as well as crystallizing and identifying fragments of Ce70 by single-crystal X-ray diffraction. Fragments show evidence for templated growth (Ce5, [Ce5(O)3(SO4)12] 10- ) and modular assembly from hexamer (Ce6) building units (Ce13, [Ce13(OH)6(O)12(SO4)14(Η2Ο)14] 6- and Ce62, [Ce62(OH)30(O)58(SO4)58] 14- ). Ce62, an almost complete ring, precipitates instantaneously in the presence of ammonium cations as two torqued arcs that interlock by hydrogen boding through NH4 +, which can also be replaced by other cations, demonstrated with CeIII. Room temperature rapid assembly of both Ce70 and Ce62, respectively, by addition of Li+ and NH4 +, along with ion?exchange and redox behavior, invite exploitation of this emerging material family in environmental and energy applications.

Isolating isostructural compounds of tetravalent metals MIV (Zr, Hf, Ce, Th, U, Pu, Np) improves our understanding of metal hydrolysis and coordination behavior across the periodic table. These metals form polynuclear clusters typified by the hexamer [MIV 6O4(OH)4]12+. Exploiting the ammonium MIV-sulfate (CeIV, ThIV, and UIV) phase space targeting rapid crystallization, we isolate the common hexamer [MIV 6(OH)4(O)4]12+ but with different numbers of capping sulfates and water molecules for CeIV, ThIV, and UIV. These phases allowed a direct comparison of bonding trends across the series. Upon cocrystallization with the hexamers, higher complex structures can be identified. Thorium features assemblies with monomer-linked hexamer chains. Uranium features assemblies with sulfate-bridged hexamers and the supramolecular assembly of 14 hexamers into the U84, [U6(OH)4(O)4)14(SO4)120(H2O)42]72–. Last, cerium showcases the isolation from monomers to the Ce62, [Ce62(OH)30(O)58(SO4)71(H2O)33.25]41−. Furthermore, small-angle X-ray scattering (room temperature) shows ammonium-induced cluster assembly for CeIV but minimal reactivity for UIV and ThIV. In this study, because the phases crystallized at elevated temperature demonstrates favorable cluster assembly, these solution phase results were surprising and suggest some other characteristics such as Ce’s facile redox behavior, contributes to its solution-phase speciation.

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After voicing a need for soul care that meets the rigors of early parenthood, this article looks to The Rule of Saint Benedict for three life-giving principles: togetherness, ordinariness, and prayer. Togetherness means not only the meta-vision of “doing” family in a larger community; it means transparency and willingness to ask for help. We learn ordinariness from Benedict through the vow of stability, which demands that our inner lives open and connect to the present moment, and also through the way Benedict honors menial tasks and vessels. The Opus Dei that the Rule weaves through all work can, for a parent, take the form of an organic Opus Dei, woven around the routines of childcare, as well as the great small-prayer practices of the church, like aspirations, Celtic prayers, the florilegia, and hesychastic prayer. These principles help early parenthood become an integral phase in our own formation and ability to care for another.