A5049005370- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Radioactive element chemistry and processing
- Lanthanide and Transition Metal Complexes
- Organometallic Complex Synthesis and Catalysis
- Magnetism in coordination complexes
- Nuclear Materials and Properties
- Nuclear materials and radiation effects
- X-ray Spectroscopy and Fluorescence Analysis
- Chemical Synthesis and Characterization
- Advanced Chemical Physics Studies
- Machine Learning in Materials Science
- Nuclear Physics and Applications
- Advanced NMR Techniques and Applications
- Chemical Thermodynamics and Molecular Structure
- Metal complexes synthesis and properties
- Supramolecular Chemistry and Complexes
- Rare-earth and actinide compounds
- Coordination Chemistry and Organometallics
- Crystallography and molecular interactions
- Chemical Reaction Mechanisms
- Nuclear reactor physics and engineering
- Synthesis and Properties of Aromatic Compounds
- Advanced Condensed Matter Physics
- Covalent Organic Framework Applications
Lawrence Berkeley National Laboratory
2020-2025
University of California, Berkeley
2020-2025
University of California System
2020-2025
Georgia Institute of Technology
2019-2020
Berkeley College
2020
AID Atlanta
2019-2020
Synthetic strategies to yield molecular complexes of high-valent lanthanides, other than the ubiquitous Ce4+ ion, are exceptionally rare, and thorough, detailed characterization in these systems is limited by complex lifetime reaction isolation conditions. The synthesis high-symmetry high purity with significant lifetimes solution solid state essential for determining role ligand-field splitting, multiconfigurational behavior, covalency governing reactivity physical properties potentially...
An isostructural series of four annulated actinocene complexes, M(hdcCOT) 2 (M = Th, U, Np, Pu), are reported.
Interest in actinide–carbon bonds has persisted since actinide organometallics were first investigated for applications isotope separation during the Manhattan Project. Transplutonium are rarely isolated and structurally characterized, likely owing to limited inventories, a scarcity of suitable laboratory infrastructure, intrinsic difficulties with anaerobic conditions required. Herein, we report discovery an organometallic “berkelocene” complex prepared from 0.3 milligrams berkelium-249....
The homoleptic complexes of cerium with the tris(piperidinyl)imidophosphorane ligand, [NP(pip)3]-, present most negative Ce3+/4+ redox couple known (<-2.64 V vs Fc/Fc+). This dramatic stabilization tetravalent oxidation state [>4.0 shift from in 1 M HClO4(aq)] is established through reactivity studies. Spectroscopic studies (UV-vis, electron paramagnetic resonance, and Ce L3-edge X-ray absorption spectroscopy), conjunction density functional theory studies, reveal dominant covalent...
A redox pair of Ce<sup>4+</sup> and Ce<sup>3+</sup> complexes, isotypic to previously prepared Tb<sup>4+</sup> Tb<sup>3+</sup> respectively, is reported establish a comparative physical spectroscopic analysis tetravalent lanthanide ions.
The 4f orbitals of Ce(IV) have shown appreciably enhanced covalent mixing with ligand relative to those Ce(III). Here, X-ray spectroscopy, magnetic susceptibility measurements, and theoretical methods are used investigate covalency in CeF
A series of solvated complexes: [(C8H8)Ln(C5Me4R)(DME)] Ln = La, R −Me; (La-2) Ce, −Me, −SiMe3, −H; (Ce-2, Ce-3, Ce-4), [(dbCOT)Ln(C5Me5)(DME)] (Ln-6), (dbCOT2– dibenzocyclooctadienide; La), [(dbCOT)Ce(C5Me4H)(DME)] (Ce-7) and [(hdcCOT)Ce(C5Me5)(DME)] (Ce-8) (hdcCOT2– hexahydrodicyclopentacyclooctatetraenide) base-free mixed-sandwich complexes [(C8H8)Ce(C5Me5)] (Ce-9), [(C8H8)Ce(C5Me4H) (Ce-10) [(hdcCOT)Ce(C5Me5)] (Ce-11) the early lanthanide metals cerium lanthanum comprising variable...
Recent studies of lanthanide bonding have shown that small amounts metal--ligand covalency can impact bond energies and cause magnetic behavior to deviate from the free ion values. Quantifying covalent parameters is necessary support rational design these properties for applications in energy information science. Here, two measurements f-electron occupancy CeBr6(2-) are reported based on X-ray spectra at Ce L3- Br K-edges compared corresponding results CeF6(2-) CeCl6(2-). These values allow...
A fundamental step toward studying the unique properties of actinide nanomaterials is control over shape nanoparticles. Toward this goal, work demonstrates effects precursor identity and surfactant concentration on uranium dioxide (UO2) UO2 nanoparticles were synthesized by thermal decomposition different precursors in presence oleylamine oleic acid as surfactants. The size, shape, phase, chemical composition was evaluated using transmission electron microscopy (TEM), energy dispersive X-ray...
ThO<sub>2</sub> and UO<sub>2</sub> nanoparticles synthesized using a COF-5 template exhibit unpassivated surfaces provide insight into nanoscale properties of actinides.
We report the synthesis and characterization of macrocyclic californium derivative Na[Cf(H
The synthesis and structural characterization of molecular complexes lanthanide iodides supported by the weak-base, diethyl ether, are reported.
Reaction of the potassium pentamethylcyclopentadienyl iridate tris-hydride K[IrCp*H3] with UCl4 and ThCl4(DME)2 led to complete replacement halide ligands generate multimetallic complexes U{(μ-H)3IrCp*}4 (1) Th{[(μ-H2)(H)IrCp*]2[(μ-H)3IrCp*]2} (2), respectively. These analogues feature a significant discrepancy in hydride bonding modes; 1 contains twelve bridging hydrides while 2 ten two terminal, Ir-bound hydrides. Use U(iii) starting material, UI3(1,4-dioxane)1.5, resulted octanuclear...
5f covalency in [U(C7H7)2]- was probed with carbon K-edge X-ray absorption spectroscopy (XAS) and electronic structure theory. The results revealed U orbital participation δ-bonding both the ground- core-excited states; additional ϕ-mixing is observed states. Comparisons U(C8H8)2 show greater δ-covalency for [U(C7H7)2]-.
Interest in actinide–carbon bonds has persisted since actinide organometallics were first targeted for isotope separation during the Manhattan Project. Sandwich complexes with cyclooctatetraenide ligands have been used extensively to form tetravalent compounds, “actinocenes,” from thorium through plutonium. These pivotal development of electronic structure models throughout inorganic chemistry. The isolation and structural characterization transplutonium is extremely challenging due limited...
Synthetic strategies to yield molecular complexes of high-valent lanthanides, other than the ubiquitous Ce<sup>4+</sup> ion, are exceptionally rare, and thorough, detailed characterization in these systems is limited by complex lifetime reaction isolation conditions. The synthesis high-symmetry high purity with significant lifetimes solution solid-state essential for determining role ligand-field splitting, multiconfigurational behavior, covalency governing reactivity physical...
A single-source-precursor approach was developed to synthesize uranium-based materials outside of the typically-studied oxides. This allows for shorter reaction times, milder conditions, and control over chemicals present in synthesis. To this end, first homoleptic uranium thioamidate complex synthesized as a precursor US
Abstract EXAFS provides the capability to interrogate nanoparticle (NP) structure in atomistic detail without relying on long‐range crystallinity. There is a limitation that averaged structural information, making it difficult separate small amount of heterogeneous from bulk. In this work, models were developed extract surface‐specific information conventional measurements collected UO 2 NPs varying size. Specifically, surface terminating species was determined comparison coordination...
Synthetic strategies to yield molecular complexes of high-valent lanthanides, other than the ubiquitous Ce 4+ ion, are exceptionally rare, and thorough, detailed characterization in these systems is limited by complex lifetime reaction isolation conditions. The synthesis high-symmetry high purity with significant lifetimes solution solid-state essential for determining role ligand-field splitting, multiconfigurational behavior, covalency governing reactivity physical properties potentially...