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The interaction of Np(V) with borate was investigated in 0.1–5.0 M NaCl and 0.25–4.5 M MgCl2 solutions with 7.2 ≤ pHm ≤ 10.0 (pHm = –log[H+]) and 0.004 M ≤ [B]tot ≤ 0.16 M. Experiments were performed under an Ar-atmosphere at T = (22 ± 2) °C using a combination of under- and oversaturation solubility experiments, NIR spectroscopy, and extensive solid phase characterization. A bathochromic shift (≈5 nm) in the Np(V) band at λ = 980 nm indicates the formation of weak Np(V)–borate complexes under mildly alkaline pHm-conditions. The identification of an isosbestic point supports the formation of a single Np(V)–borate species in dilute MgCl2 systems, whereas a more complex aqueous speciation (eventually involving the formation of several Np(V)–borate species) is observed in concentrated MgCl2 solutions. The solubility of freshly prepared NpO2OH(am) remained largely unaltered in NaCl and MgCl2 solutions with [B]tot = 0.04 M within the timeframe of this study (t ≤ 300 days). At [B]tot = 0.16 M, a kinetically hindered but very significant drop in the solubility of Np(V) (3–4 log10-units, compared to borate-free systems) was observed in NaCl and dilute MgCl2 solutions with pHm ≤ 9. The drop in the solubility was accompanied by a clear change in the colour of the solid phase (from green to white-greyish). XRD and TEM analyses showed that the amorphous NpO2OH(am) “starting material” transformed into crystalline solid phases with similar XRD patterns in NaCl and MgCl2 systems. XPS, SEM–EDS and EXAFS further indicated that borate and Na/Mg participate stoichiometrically in the formation of such solid phases. Additional undersaturation solubility experiments using the newly formed Na–Np(V)–borate(cr) and Mg–Np(V)–borate(cr) compounds further confirmed the low solubility ([Np(V)]aq ≈ 10−6–10−7 M) of such solid phases in mildly alkaline pHm-conditions. The formation of these solid phases represents a previously unreported retention mechanism for the highly mobile Np(V) under boundary conditions (pHm, [B]tot, ionic strength) of relevance to certain repository concepts for nuclear waste disposal.

Searching for actinide decorporation agents with advantages of high decorporation efficiency, minimal biological toxicity, and high oral efficiency is crucial for nuclear safety and the sustainable development of nuclear energy. Removing actinides deposited in bones after intake is one of the most significant challenges remaining in this field because of the instantaneous formation of highly stable actinide phosphate complexes upon contact with hydroxyapatite. Here we report a hydroxypyridinone-based ligand (5LIO-1-Cm-3,2-HOPO) exhibiting stronger affinity for U(VI) compared with the reported tetradentate hydroxypyridinone ligands. This is further revealed by the first principles calculation analysis on bonding between the ligand and uranium. Both in vitro uranium removal assay and in vivo decorporation experiments with mice show that 5LIO-1-Cm-3,2-HOPO can remove uranium from kidneys and bones with high efficiencies, while the decorporation efficiency is nearly independent of the treatment time. Moreover, this ligand shows a high oral decorporation efficiency, making it attractive for practical applications., In vivo decorporation of U(VI) from bones is an unsolved challenge because of the formation of stable uranium phosphate complexes. Here, the authors develop a hydroxypyridonone-based ligand with strong uranium complexation and low cytotoxicity. They find this ligand effectively removes uranium from kidney and bones in mice, and is suitable for oral administration.

We report here the investigation of using a luminescent europium organic framework, [Eu2(MTBC)(OH)2(DMF)3(H2O)4]·2DMF·7H2O (denoted as compound 1), for detecting of both Cu2+ and UO22+ with high sensitivity. Based on the spectroscopy analysis, compound 1 could selectively respond to Cu2+ and UO22+ ions among other selected monovalent, divalent, trivalent metal cations based on a turn-off mechanism. The detection limit of compound 1 towards Cu2+ ion was as low as 17.2 μg/L, which is much lower than the maximum tolerable concentration of Cu2+ in drinking water (2 mg/L) defined by United States Environmental Protection Agency. On the other hand, the detection limit towards UO22+ ions is 309.2 μg/L, which could be used for detecting uranium in relative severely contaminated areas. The concentration-dependent luminescence intensity evolution process could be fully understood by the absorption kinetics and isotherm investigations. Furthermore, the quenching mechanism was elucidated by the UV-vis, excitation, luminescence, and lifetime studies. Compound 1, as the first MOF based luminescence probe for both Cu2+ and UO22+ ions, provides insight into developing MOF-based multifunctional sensors for both nonradioactive and radioactive elements.

State of the art radio frequency (RF) arrays are growing larger in pursuit of increased signal-to-noise ratio. In support of this goal, elaborate forms of metrology are being developed to support the increased footprints. This work provides a unique solution to fulfill the metrology requirements of large-scale deployable RF antennas through the implementation of neural network demodulation of fiber optic strain sensors. The fiber optics are patterned with fiber Bragg gratings (FBGs) to encode strain on to back-reflected shifts in the wavelength of incident light. Experiments show the neural network can predict the deformation of a test structure within single millimeters for small amplitude motions. Therefore, the current technique meets the required λ / 20 precision needed for large scale deployable RF arrays operating at S-band or longer wavelengths.

Direct removal of 99TcO4− from the highly acidic solution of used nuclear fuel is highly beneficial for the recovery of uranium and plutonium and more importantly aids in the elimination of 99Tc discharge into the environment. However, this task represents a huge challenge given the combined extreme conditions of super acidity, high ionic strength, and strong radiation field. Here we overcome this challenge using a cationic polymeric network with significant TcO4− uptake capabilities in four aspects: the fastest sorption kinetics, the highest sorption capacity, the most promising uptake performance from highly acidic solutions, and excellent radiation-resistance and hydrolytic stability among all anion sorbent materials reported. In addition, this material is fully recyclable for multiple sorption/desorption trials, making it extremely attractive for waste partitioning and emergency remediation. The excellent TcO4− uptake capability is elucidated by X-ray absorption spectroscopy, solid-state NMR measurement, and density functional theory analysis on anion coordination and bonding., Direct removal of 99TcO4− from highly radioactive and acidic nuclear waste solutions is beneficial for uranium and plutonium recovery and radioactive pollution control but this represents a huge challenge. Here the authors show a cationic polymeric network with high 99TcO4− sorption capability and stability.

A luminescent lanthanide metal–organic framework [Tb7(OH)8(H2O)6(IDA)3(COO)3]·4Cl·2H2O (Tb-IDA, IDA = iminodiacetic acid) was hydrothermally synthesized and structurally characterized. Monitoring ultraviolet radiation was achieved by correlating the dosage with the luminescence color change in doped Gd99Tb0.1Eu0.9-IDA compound. A linear relationship is developed across a broad range from blue to yellow within a CIE chromaticity diagram.

Searching for cationic extended materials with a capacity for anion exchange resulted in a unique thorium molybdate chloride (TMC) with the formula of [Th(MoO4)(H2O)4Cl]Cl·H2O. The structure of TMC is composed of zigzagging cationic layers [Th(MoO4)(H2O)4Cl]+ with Cl- as interlamellar charge-balancing anions. Instead of performing ion exchange, alkali thorium fluorides were formed after soaking TMC in AF (A = Na, K, and Cs) solutions. The mechanism of AF immobilization is elucidated by the combination of SEM-EDS, PXRD, FTIR, and EXAFS spectroscopy. It was observed that four water molecules coordinating with the Th4+ center in TMC are vulnerable to competition with F-, due to the formation of more favorable Th-F bonds compared to Th-OH2. This leads to a single crystal-to-polycrystalline transformation via a pathway of recrystallization to form alkali thorium fluorides.

Although comprehensive progress has been made in the area of coordination polymer (CP)/metal-organic framework (MOF)-based proton-conducting materials over the past decade, searching for a CP/MOF with stable, intrinsic, high anhydrous proton conductivity that can be directly used as a practical electrolyte in an intermediate-temperature proton-exchange membrane fuel cell assembly for durable power generation remains a substantial challenge. Here, we introduce a new proton-conducting CP, (NH4)3[Zr(H2/3PO4)3] (ZrP), which consists of one-dimensional zirconium phosphate anionic chains and fully ordered charge-balancing NH4+ cations. X-ray crystallography, neutron powder diffraction, and variable-temperature solid-state NMR spectroscopy suggest that protons are disordered within an inherent hydrogen-bonded infinite chain of acid-base pairs (N-H···O-P), leading to a stable anhydrous proton conductivity of 1.45 × 10-3 S·cm-1 at 180 °C, one of the highest values among reported intermediate-temperature proton-conducting materials. First-principles and quantum molecular dynamics simulations were used to directly visualize the unique proton transport pathway involving very efficient proton exchange between NH4+ and phosphate pairs, which is distinct from the common guest encapsulation/dehydration/superprotonic transition mechanisms. ZrP as the electrolyte was further assembled into a H2/O2 fuel cell, which showed a record-high electrical power density of 12 mW·cm-2 at 180 °C among reported cells assembled from crystalline solid electrolytes, as well as a direct methanol fuel cell for the first time to demonstrate real applications. These cells were tested for over 15 h without notable power loss.

The combination of high atomic number and high oxidation state in UVI materials gives rise to both high X-ray attenuation efficiency and intense green luminescence originating from ligand-to-metal charge transfer. These two features suggest that UVI materials might act as superior X-ray scintillators, but this postulate has remained substantially untested. Now the first observation of intense X-ray scintillation in a uranyl-organic framework (SCU-9) that is observable by the naked eye is reported. Combining the advantage in minimizing the non-radiative relaxation during the X-ray excitation process over those of inorganic salts of uranium, SCU-9 exhibits a very efficient X-ray to green light luminescence conversion. The luminescence intensity shows an essentially linear correlation with the received X-ray intensity, and is comparable with that of commercially available CsI:Tl. SCU-9 possesses an improved X-ray attenuation efficiency (E>20 keV) as well as enhanced radiation resistance and decreased hygroscopy compared to CsI:Tl.

Actinide based metal-organic frameworks (MOFs) are unique not only because compared to the transition-metal and lanthanide systems they are substantially less explored, but also owing to the uniqueness of actinide ions in bonding and coordination. Now a 3D thorium-organic framework (SCU-11) contains a series of cages with an effective size of ca. 21×24 A. Th4+ in SCU-11 is 10-coordinate with a bicapped square prism coordination geometry, which has never been documented for any metal cation complexes. The bicapped position is occupied by two coordinated water molecules that can be removed to afford a very unique open Th4+ site, confirmed by X-ray diffraction, color change, thermogravimetry, and spectroscopy. The degassed phase (SCU-11-A) exhibits a Brunauer-Emmett-Teller surface area of 1272 m2 g-1 , one of the highest values among reported actinide materials, enabling it to sufficiently retain water vapor, Kr, and Xe with uptake capacities of 234 cm3 g-1 , 0.77 mmol g-1 , 3.17 mmol g-1 , respectively, and a Xe/Kr selectivity of 5.7.

The accurate detection of UV radiation is required in a wide range of chemical industries and environmental or biological related applications. Conventional methods taking advantage of semiconductor photodetectors suffer from several drawbacks such as sophisticated synthesis and manufacturing procedure, not being able to measure the accumulated UV dosage as well as high defect density in the material. Searching for new strategies or materials serving as precise UV dosage sensor with extremely low detection limit is still highly desirable. In this work, a radiation resistant uranium coordination polymer [UO2(L)(DMF)] (L = 5-nitroisophthalic acid, DMF = N,N-dimethylformamide, denoted as compound 1) was successfully synthesized through mild solvothermal method and investigated as a unique UV probe with the detection limit of 2.4 × 10-7 J. On the basis of the UV dosage dependent luminescence spectra, EPR analysis, single crystal structure investigation, and the DFT calculation, the UV-induced radical quenching mechanism was confirmed. Importantly, the generated radicals are of significant stability which offers the opportunity for measuring the accumulated UV radiation dosage. Furthermore, the powder material of compound 1 was further upgraded into membrane material without loss in luminescence intensity to investigate the real application potentials. To the best of our knowledge, compound 1 represents the most sensitive coordination polymer based UV dosage probe reported to date.

The exploration of phase formation in the f-element-bearing iodate selenate system has resulted in 14 novel rare-earth-containing iodate selenates, Ln(IO3)(SeO4) (Ln = La, Ce, Pr, Nd; LnISeO-1), Ln(IO3)(SeO4)(H2O) (Ln = Sm, Eu; LnISeO-2), and Ln(IO3)(SeO4)(H2O)2·H2O (Ln = Gd, Dy, Ho, Er, Tm, Yb, Lu, Y; LnISeO-3), as well as two new thorium iodate selenates, Th(OH)(IO3)(SeO4)(H2O) (ThISeO-1) and Th(IO3)2(SeO4) (ThISeO-2). LnISeO-3 and ThISeO-2 crystallize in the chiral space group P212121, while LnISeO-1, LnISeO-2, and ThISeO-1 crystallize in the centrosymmetric space group P21/c. The numbers of both coordinating and hydrating water molecules crystallized in LnISeO-1, LnISeO-2, and LnISeO-3 increase along these three series, in line with the increasingly negative values of hydration enthalpies of heavier trivalent lanthanide ions. Such a systematic change in compositions, especially the first coordination sphere of Ln, further induces structural rearrangements, including coordination number and dimensional reductions. More specifically, the structures of LnISeO-1, LnISeO-2, and LnISeO-3 have undergone transitions from 2D Ln-oxo layers with 10-coordinate Ln centers to 1D Ln-oxo chains with 9-coordinate Ln centers and then to 0D Ln-oxo monomers with 8-coordinate Ln centers, respectively. The formation and characterization of this large family of Ln/Th iodate selenates suggest that such a mixed-anion system not only exhibits richer structural chemistry but also can be capable of generating intriguing properties, such as the second-harmonic generation (SHG) effect.

During the current period of rapid technological change, business students need to emerge from their introductory course in Information Systems (IS) with a set of fundamental principles to help them “think about Information Technology (IT)” in future courses and the workplace. Given the digital revolution, they also need to appreciate the role of information in business as well has how to meet the challenges involved in managing information effectively. This paper addresses both those needs by presenting a fundamental principle concerning information management: How you store information affects how you can retrieve it. The paper commences by presenting the principle in a manner that can be used to introduce it to the class. It continues by providing numerous concepts and examples that draw on the principle and that students are likely to encounter in the core IS course, subsequent courses, and their real-world use of technology. The paper concludes by raising a set of issues suitable for class discussion or exam questions.

The first heterobimetallic uranium(IV)/vanadium(III) phosphite compound, Na2UV2(HPO3)6 (denoted as UVP), was synthesized via an in situ redox-active hydrothermal reaction. It exhibits superior hydrolytic and antioxidant stability compared to the majority of structures containing low-valent uranium or vanadium, further elucidated by first-principles simulations, and therefore shows potential applications in nuclear waste management.

When exposed to water, the two-dimensional uranyl-organic layered compound [(CH3)2NH2][(UO2)(BCPBA)]·2DMF·H2O (H3BCPBA = 3,5-bis (4'-carboxylphenoxy) benzoic acid) gradually undergoes a complete single-crystal-to-single-crystal phase transition to [(CH3)2NH2][(UO2)(BCPBA)]·3.4H2O, resulting in an enhanced ligand-ligand interaction between the adjacent layers. This process gives rise to initial quenching of the uranyl photoluminescence followed by subsequent recovery of the photoluminescence with a much elevated intensity, as a unique case of aggregation-induced emission in an extended solid system, further confirmed by DFT analysis on bonding.

Although no evident hydrogen-bond network appears, an ultrahigh proton conductivity of 2.91 × 10-2 S cm-1 at 363 K and 90% RH with an ultralow activation energy of 0.10 eV was observed in an anionic lanthanide-organic framework Na2[Eu(SDB)2(COO)]·0.375DMF·0.4H2O (1); both values approach the records among all reported proton-conducting MOF materials. This suggests that the proton conduction process in 1 is reminiscent of the Grotthuss mechanism, which together reveals an effective proton transportation pathway associated with aligned Na+ and their coordinated water.

We present a depleted uranium-based metal organic framework, UO2(C8H3O6N)·DMF, that exhibits highly sensitive and selective detection towards Fe3+ ions in aqueous media with an extremely low detection limit of 6.3 ppb. This work offers insight into exploring the potential applications of actinide-based metal organic frameworks in the area of chemical sensing with intrinsic advantages of high selectivity and sensitivity.

Effective and selective removal of 99TcO4– from aqueous solution is highly desirable for both waste partitioning and contamination remediation purposes in the modern nuclear fuel cycle, but is of significant challenge. We report here a hydrolytically stable and radiation-resistant cationic metal–organic framework (MOF), SCU-101, exhibiting extremely fast removal kinetics, exceptional distribution coefficient, and high sorption capacity toward TcO4–. More importantly, this material can selectively remove TcO4– in the presence of large excesses of NO3– and SO42–, as even 6000 times of SO42– in excess does not significantly affect the sorption of TcO4–. These superior features endow that SCU-101 is capable of effectively separating TcO4– from Hanford low-level waste melter off-gas scrubber simulant stream. The sorption mechanism is directly unraveled by the single crystal structure of TcO4–-incorporated SCU-101, as the first reported crystal structure to display TcO4– trapped in a sorbent material. A recogni...

The synthesis, structure elucidation, and spectroscopic measurements of a myriad of new, f-element borates has revealed the unusual effects that this electron-rich oxoanion has on the electronic properties of lanthanides and actinides. One purpose of these studies was to provide models for actinide compounds that may exist in either vitrified nuclear waste or in repositories located within salt deposits that have significant borate content. In addition, the radiation-damage resilience of polyborate networks positions these materials as suitable candidates for probing coordination chemistry and physical properties much deeper into the actinide series than is normally possible, and compounds with actinides up to californium (Z = 98) have been successfully prepared and characterized in exquisite detail. Structural determination of these materials show that both the lanthanide and actinide series display previously unknown coordination chemistry, but, more importantly, that the two series have little overlap in terms of structure and composition, and have few parallels. In addition, some of these compounds display unique physico-chemical properties, one example of which is the selective trapping of radionuclides. The foremost discovery first identified in actinide borates is that the chemistry of californium represents an onset of unprecedented chemical behavior that compares better with high-oxidation state, early transition metal complexes than it does with earlier f-elements.

Uranium is unique owing not only to its intriguing physiochemical properties, but also to the diverse coordination chemistry that uranyl adopts and bonding that enables rich and unpredictable topologies of uranium-bearing materials. Six anionic uranium oxyfluorides with various dimensionalities, including a 3D framework (MeUF), four 2D lamellar structures (EtUF-1, PrUF, BuUF-1, and BuUF-2), and a 1D chained topology (EtUF-2), have been rationally constructed by employing tetra-alkyl ammonium ions as structure-directing agents. By combining the tunable interlayer distance of the lamellar structures with the photooxygenation properties of uranyl ions, a bifunctional platform for highly selective ion-exchange and photocatalytic degradation over organic dyes has been developed. Specifically, BuUF-2 can efficiently capture 94.5% methylene blue (MB+) within 24 h from solution with remarkable selectivity related to both the size and the charge of organic dyes. Such size- and charge-dependent selectivity toward organic dyes has been documented for MOFs, but is rare for 2D lamellar materials. Furthermore, the removal of MB+ can be largely accelerated under UV radiation (e.g. 84.7% for BuUF-2 within 1 h) due to the photocatalytic activities of EtUF-1, EtUF-2, PrUF, and BuUF-2.

We report here the investigation of using a luminescent europium organic framework, [Eu

Deferiprone (3-hydroxy-1,2-dimethyl-4(1H)-pyridone, DFP), which is a drug clinically used for removing heavy metals in vivo, was explored for its removal efficiency towards uranium. The reaction of uranyl nitrate hexahydrate with DFP at room temperature yielded the compound [(UO2)(H2O)(C7NO2H8)2]·4H2O (1), which crystallizes from a mixed solution of methanol and water (pH = 7.0). X-ray diffraction shows that the stable complexation of uranyl occurs from the coordination of two bidentate DFP ligands perpendicular to the O[double bond, length as m-dash]U[double bond, length as m-dash]O unit with a fifth coordinating oxygen atom coming from one water molecule, resulting in a pentagonal bipyramidal geometry. The formation constants of uranyl and DFP complexes were measured and the species distribution diagram illustrates that UO2L2 (94.6%) is the dominant uranyl-DFP complex in 0.1 M KCl solution at physiological pH = 7.4. The results from both crystallographic and potentiometric studies imply that the metal : ligand ratio is 1 : 2. The effectiveness of using DFP to remove uranium was examined at the cellular level, and the results suggest that it can significantly reduce the cellular uptake and increase the cellular release of U(vi) in renal proximal tubular epithelial cells (NRK-52E).

Searching for cationic extended materials with a capacity for anion exchange resulted in a unique thorium molybdate chloride (TMC) with the formula of [Th(MoO

By utilizing zinc amalgam as an in situ reductant and pH regulator, mild hydrothermal reaction between UO2(CH3COO)2·2H2O, H2SO4, and Cs2CO3 or between UO2(CH3COO)2·2H2O, C2H4(SO3H)2, and K2CO3 yielded a novel cesium UIV sulfate trimer Cs4[U3O(SO4)7]·2.2H2O (1) and a new potassium UIV disulfonic hexamer K[U6O4(OH)5(H2O)5][C2H4(SO3)2]6·6H2O (2), respectively. Compound 1 features a lamellar structure with a honeycomb lattice, and it represents an unprecedented trimeric UIV cluster composed of purely inorganic moieties. Complex 2 is built from hexanuclear U4+ cores and K+ ions interconnected by μ5-[C2H4(SO3)2]2– groups, leading to the construction of an extended framework rather than commonly observed discrete, neutral molecular sulfonate clusters. The various binding modes of the sulfate and disulfonate groups, especially the multidentate ones, enable additional bridging between metal ions, which promotes oligomerization and isolation of polynuclear species. Furthermore, compound 1 exhibits both ion-exchange...

Real-time and accurate detection of pH in aqueous solution is of great significance in chemical, environmental, and engineering-related fields. We report here the use of 8-hydroxyquinoline-functionalized covalent organic framework (COF-HQ) for dual-mode pH sensing. In the fluorescent mode, the emission intensity of COF-HQ weakened as the pH decreased, and also displayed a good linear relationship against pH in the range from 1 to 5. In addition, COF-HQ showed discernible color changes from yellow to black as the acidity increased and can be therefore used as a colorimetric pH sensor. All these changes are reversible and COF-HQ can be recycled for multiple detection runs owing to its high hydrolytical stability. It can be further assembled into a mixed matrix membrane for practical applications.

Eighteen new lanthanide transition metal heterobimetallic compounds, Ln2Co(TeO3)2(SO4)2 (Ln = Y, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu) and Ln2Zn(TeO3)2(SO4)2 (Ln = Sm, Gd, Dy, Ho, Er, or Yb), have been prepared. They crystallize in triclinic space group P1 with two different structural topologies occurring because of a reduction in the Ln3+ coordination number from eight to seven with the smallest lanthanides, Yb3+ and Lu3+. Magnetic susceptibility studies of compounds with diamagnetic lanthanides and lanthanide-like ions suggest that antiferromagnetic interactions occur between the Co2+ ions. Similarly, the replacement of Co2+ with Zn2+ yields Ln2Zn(TeO3)2(SO4)2 (Ln = Gd, Dy, Ho, or Er), and these materials allow for the resolution of the nature of the interactions between lanthanide ions. The data suggest that the short-range Ln3+···Ln3+ interactions are ferromagnetic. However, a wide range of ferro- and antiferromagnetic interactions occur between the Ln3+ and the Co2+ cations, with several c...

The complexation of UO2(2+) by formohydroxamate (FHA(-)) creates solutions with dark red coloration. The inherent redox activity of formohydroxamate leads to the possibility that these solutions contain U(V) complexes, which are often red. We demonstrate that the reaction of U(VI) with formohydroxamate does not result in reduction, but rather in formation of the putative cis-aquo UO2(FHA)2(H2O)2, whose polymeric solid-state structure, UO2(FHA)2, contains an unusually bent UO2(2+) unit and a highly distorted coordination environment around a U(VI) cation in general. The bending of the uranyl cation results from unusually strong π donation from the FHA(-) ligands into the 6d and 5f orbitals of the U(VI) cation. The alteration of the bonding in the uranyl unit drastically changes its electronic and vibrational features.

There have been numerous studies on emission-color regulation by the adjustment of molar amounts of multiple trivalent lanthanide cations, such as Eu3+, Tb3+, Dy3+, and others, in many types of solid host materials. Although uranyl emission originating from charge-transfer transitions has been well-recognized and investigated for many decades, as of now there is no report on tunable 4f/5f bimodal emission based on heterobimetallic lanthanide(III) and uranyl(VI) compounds. In most cases, complete energy transfer between uranyl(VI) and lanthanide(III) centers was observed. In this work, a series of isotypic-europium-incorporated uranyl coordination polymers, Eu@UO2L(DMF) (L2– = 3,5-pyridinedicarboxylate, denoted as 1–10, which represent the different Eu contents in UO2L(DMF); DMF = N,N-dimethylformamide), has been synthesized by solvothermal reactions. Crystallographic evidence of this series unveiled one-dimensional chains of UO22+ as pentagonal-bipyramidal units bridged by pyridinedicarboxylate with no de...

We present a depleted uranium-based metal organic framework, UO

In this Frontier article, we pursue the sequestration of radionuclides from aqueous solution by using recently emerging metal-organic framework (MOF) materials. The design of MOF materials and their corresponding sorption properties towards radionuclides (137Cs, 90Sr, 238U, 79Se, and 99Tc) as well as their interaction mechanisms are highlighted. The present challenges and future prospects of removing radionulides with MOFs as sorbents are also demonstrated.

Effective and selective removal of

bibtex: ISI:000412043000020 bibtex\location:'1155 16TH ST, NW, WASHINGTON, DC 20036 USA',publisher:'AMER CHEMICAL SOC',type:'Article',affiliation:'Albrecht-Schmitt, TE (Reprint Author), Florida State Univ, Dept Chem & Biochem, Tallahassee, FL 32306 USA. Silver, Mark A.; Cary, Samantha K.; Arico, Alexandra A.; Galmin, Gregory A.; Wang, Jamie C.; Clark, Ronald J.; Chemey, Alexander; Eaton, Teresa M.; Marsh, Matthew L.; Seidler, Kevin; Galley, Shane S.; van de Burgt, Lambertus; Hobart, David E.; Hanson, Kenneth; Albrecht-Schmitt, Thomas E., Florida State Univ, Dept Chem & Biochem, Tallahassee, FL 32306 USA. Garza, Alejandro J.; Scuseria, Gustavo E., Rice Univ, Dept Chem, POB 1892, Houston, TX 77251 USA. Baumbach, Ryan E.; Chen, Kuan-Wen, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. Johnson, Jason A.; Gray, Ashley L., Florida State Univ, Environm Hlth & Safety, Tallahassee, FL 32306 USA. Van Cleve, Shelley M., Oak Ridge Natl Lab, Nucl Mat Proc Grp, One Bethel Valley Rd, Oak Ridge, TN 37830 USA. Gendron, Frederic; Autschbach, Jochen, Univ Buffalo State Univ New York, Dept Chem, Buffalo, NY 14260 USA. Maron, Laurent, Inst Natl Sci Appl, Lab Phys & Chim Nanoobjets, F-31077 Toulouse 4, France. Speldrich, Manfred; Koegerler, Paul, Rhein Westfal TH Aachen, Inst Anorgan Chem, D-52074 Aachen, Germany. Celis-Barros, Cristian; Paez-Hernandez, Dayan; Arratia-Perez, Ramiro, Univ Andres Bello, Fac Ciencias Exactas, Ctr Nanociencias Aplicadas, Republ 275, Santiago, Chile. Ruf, Michael, Bruker AXS, 5465 East Cheryl Pkwy, Madison, WI 53711 USA.','author-email':'albrecht-schinitt@chem.fsu.edu',da:'2018-12-05','doc-delivery-number':'FI5SB','funding-acknowledgement':'U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Heavy Elements Chemistry Program [DE-FG02-13ER16414, DE-SC0001136, DE-FG02-04ER15523]; Welch Foundation Chair [C-0036]; National Science Foundation [DMR-1157490, DGE-1449440]; State of Florida; U.S. Department of Energy; CBFO Fellowship Program (MAS) - U.S. Department of Energy','funding-text':'This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Heavy Elements Chemistry Program, under Award Numbers DE-FG02-13ER16414 (FSU), DE-SC0001136 (formerly DE-FG02-09ER16066) (FG & JA), and DE-FG02-04ER15523 (G.E.S). G.E.S. is a Welch Foundation Chair (Grant No. C-0036). The isotopes used in this research were supplied by the U.S. Department of Energy, Office of Science, by the Isotope Program in the Office of Nuclear Physics. The \textlessSUP\textgreater249\textless/SUP\textgreaterBk was provided to Florida State University by the Isotope Development and Production for Research and Applications Program through the Radiochemical Engineering and Development Center at Oak Ridge National Laboratory. Magnetization measurements using the VSM SQUID MPMS were performed at the National High Magnetic Field Laboratory, which is supported by National Science Foundation Cooperative Agreement No. DMR-1157490, the State of Florida, and the U.S. Department of Energy. This research is supported in part by an appointment to the CBFO Fellowship Program (MAS), sponsored by the U.S. Department of Energy and administered by the Oak Ridge Institute for Science and Education. Jamie Wang is supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1449440.','journal-iso':'J. Am. Chem. Soc.','keywords-plus':'VALENCE BASIS-SETS; ENERGY-ADJUSTED PSEUDOPOTENTIALS; MOLECULAR-ORBITAL METHODS; CRYSTAL-STRUCTURE; AB-INITIO; MAGNETIC-SUSCEPTIBILITY; COORDINATION GEOMETRY; PERTURBATION-THEORY; IONIC-RADII; PLUTONIUM','number-of-cited-references':'113',oa:'Bronze','orcid-numbers':'Kogerler, Paul/0000-0001-7831-3953 Gendron, Frederic/0000-0002-1896-3978 Hanson, Kenneth/0000-0001-7219-7808 Albrecht-Schmitt, Thomas/0000-0002-2989-3311 Chemey, Alexander/0000-0002-0679-7845 Paez, Dayan/0000-0003-2747-9982 Speldrich, Manfred/0000-0002-8626-6410 Celis-Barros, Cristian/0000-0002-4685-5229 Garza, Alejandro/0000-0001-6995-2833','research-areas':'Chemistry','researcherid-numbers':'Kogerler, Paul/H-5866-2013','times-cited':'5','unique-id':'ISI:000412043000020','usage-count-last-180-days':'8','usage-count-since-2013':'36','web-of-science-categories':'Chemistry, Multidisciplinary'\; International audience; The reaction of Bk-249(OH)(4) with iodate under hydro thermal conditions results in the formation of Bk(IO3)(3) as the major product with trace amounts of Bk(IO3)(4) also crystallizing from the reaction mixture. The structure of Bk(Io(3))(3) consists of nine-coordinate BO cations that are bridged by iodate anions to yield layers that are isomorphous with those found for Am-III, Cf-III, and with lanthanides that possess similar ionic radii. Bk(IO3)(4) was expected to adopt the same structure as M(IO3)(4) (M = Ce, Np, Pu), but instead parallels the structural chemistry of the smaller Zr-IV cation. Bk-III-O and Bk-IV-O bond lengths are shorter than anticipated and provide further support for a postcurium break in the actinide series. Photoluminescence and absorption spectra collected from single crystals of Bk(IO3)(4) show evidence for doping with Bkill in these crystals. In addition to luminescence from Bkul in the Bk(IO3)(4) crystals, a broad-band absorption feature is initially present that is similar to features observed in systems with intervalence charge transfer. However, the high-specific activity of Bk-249 (t(1/2) = 320 d) causes oxidation of Bk-III and only Bk-IV is present after a few days with concomitant loss of both the Bk-III luminescence and the broadband feature. The electronic structure of Bk(IO3)(3) and Bk(IO3)(4) were examined using a range of computational methods that include density functional theory both on clusters and on periodic structures, relativistic ab initio wave function calculations that incorporate spin orbit coupling (CASSCF), and by a full-model Hamiltonian with spin-orbit coupling and Slater-Condon parameters (CONDON). Some of these methods provide evidence for an asymmetric ground state present in Bk-IV that does not strictly adhere to Russel Saunders coupling and Hund's Rule even though it possesses a half-filled Sf(7) shell. Multiple factors contribute. to the asymmetry that include 5f electrons being present in microstates that are not solely spin up, spin-orbit coupling induced mixing of low-lying excited states with the ground state, and covalency in the Bk-IV-O bonds that distributes the 5f electrons onto the ligands. These factors are absent or diminished in other f(7) ions such as Gd-III or Cm-III.

The reaction of formohydroxamic acid [NH(OH)CHO, FHA] with Pu(III) should result in stabilization of the trivalent oxidation state. However, slow oxidation to Pu(IV) occurs, which leads to formation of the dimeric plutonium(IV) formohydroxamate complex Pu2(FHA)8. In addition to being reductants, hydroxamates are also strong π-donor ligands. Here we show that formation of the Pu2(FHA)8 dimer occurs via covalency between the 5f orbitals on plutonium and the π* orbitals of FHA(-) anions, which gives rise to a broad and intense ligand-to-metal charge-transfer feature. Time-dependent density functional theory calculations corroborate this assignment.