A5033721117- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Radioactive element chemistry and processing
- Crystallography and molecular interactions
- Organometallic Complex Synthesis and Catalysis
- Lanthanide and Transition Metal Complexes
- Coordination Chemistry and Organometallics
- Magnetism in coordination complexes
- Nuclear Materials and Properties
- Chemical Synthesis and Characterization
- Synthesis and characterization of novel inorganic/organometallic compounds
- Inorganic Chemistry and Materials
- Asymmetric Hydrogenation and Catalysis
- Rare-earth and actinide compounds
- Metal complexes synthesis and properties
- Nuclear materials and radiation effects
- Polyoxometalates: Synthesis and Applications
- Organic and Molecular Conductors Research
- Crystal structures of chemical compounds
- Radiopharmaceutical Chemistry and Applications
- Iron-based superconductors research
- Metal-Organic Frameworks: Synthesis and Applications
- Crystal Structures and Properties
- Carbon dioxide utilization in catalysis
- Catalysis and Oxidation Reactions
Los Alamos National Laboratory
2015-2024
Los Alamos Medical Center
2010-2020
National Physical Laboratory
2018
Los Alamos National Security (United States)
2017
Virginia Tech
2007-2016
University of Ottawa
2011
Ocean Institute
2010
Oceanit (United States)
2010
Rutherford Appleton Laboratory
2010
University of Oxford
2010
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEthylene polymerization by a cationic dicyclopentadienyl zirconium(IV) alkyl complexRichard F. Jordan, Chandrasekhar S. Bajgur, Roger. Willett, and Brian. ScottCite this: J. Am. Chem. Soc. 1986, 108, 23, 7410–7411Publication Date (Print):November 1, 1986Publication History Published online1 May 2002Published inissue 1 November 1986https://pubs.acs.org/doi/10.1021/ja00283a047https://doi.org/10.1021/ja00283a047research-articleACS PublicationsRequest...
A series of ionic liquids containing different paramagnetic anions have been prepared and all show behavior with potential applications for magnetic electrochromic switching as well novel transport; also, the tetraalkylphosphonium-based reveal anomalous behavior.
A cationic cobalt(II)–alkyl complex is an effective precatalyst for hydrogenation of alkenes, aldehydes, ketones, and imines under mild conditions (1–4 atm H2; see scheme). The catalyst shows a high functional-group tolerance across broad range substrates. Experiments suggest that the active catalytic species cobalt(II)–hydride complex.
Cobalt(II) alkyl complexes of aliphatic PNP pincer ligands have been synthesized and characterized. The cationic cobalt(II) complex [(PNHPCy)Co(CH2SiMe3)]BArF4 (4) (PNHPCy = bis[(2-dicyclohexylphosphino)ethyl]amine) is an active precatalyst for the hydrogenation olefins ketones acceptorless dehydrogenation alcohols. To elucidate possible involvement N–H group on ligand in catalysis via a metal–ligand cooperative interaction, reactivities 4 [(PNMePCy)Co(CH2SiMe3)]BArF4 (7) were compared....
Covalency in Ln–Cl bonds of Oh-LnCl6x– (x = 3 for Ln CeIII, NdIII, SmIII, EuIII, GdIII; x 2 CeIV) anions has been investigated, primarily using Cl K-edge X-ray absorption spectroscopy (XAS) and time-dependent density functional theory (TDDFT); however, Ce L3,2-edge M5,4-edge XAS were also used to characterize CeCl6x– 2, 3). The spectra modeled configuration interaction calculations. results evaluated as a function (1) the lanthanide (Ln) metal identity, which was varied across series from...
Solution-processed 2D perovskite diodes with fully depleted junction enable highly sensitive and robust thin-film x-ray detectors.
The reaction of 3-amino-5-nitro-1,2,4-triazole with nitrous acid produces the corresponding diazonium salt. When salt is treated nitroacetonitrile, a subsequent condensation and cyclization occurres to produced 4-amino-3,7-dinitrotriazolo-[5,1-c][1,2,4] triazine (DPX-26). X-ray crystallographic analysis shows that DPX-26 has density 1.86 g cm-3 , while it calculated have heat formation 398.3 kJ mol-1 . predicted approach explosive performance RDX but displays significantly better safety...
UTe2 is a newly-discovered unconventional superconductor wherein multicomponent topological superconductivity anticipated based on the presence of two superconducting transitions and time-reversal symmetry breaking in state. The observation transitions, however, remains controversial. Here we demonstrate that single crystals displaying an optimal transition temperature at 2 K exhibit remarkably high quality supported by their small residual heat capacity state large resistance ratio. Our...
The ’’tracking procedure’’ is a method to train and evaluate the reception of ongoing speech. A talker receiver engage in dialogue for designated period time which reports his perception successive segments read text corrected by until repeated verbatim. Performance measured number words correctly per unit time. procedure illustrated its application project training evaluating use vibrotactile–electrotactile aid lipreading. Differences between experimental conditions are described over terms...
Going full circle: Ammonia borane is a potential H2-releasing fuel. Polyborazylene, form of the spent fuel, can be regenerated efficiently in one-pot process by stepwise addition appropriate digesting and reducing agents. A unique feature this formation NH3, which retained some digested species. Detailed facts importance to specialist readers are published as "Supporting Information". Such documents peer-reviewed, but not copy-edited or typeset. They made available submitted authors. Please...
No foaming at the mouth here: A calcium(II) derivative of ammonia–borane, Ca(NH2BH3)2 (see picture; green Ca, red O, blue N, yellow B, gray C, small H), has thermal properties that are quite different from those ammonia–borane. releases hydrogen over a temperature range 100 to 170 °C without foaming.
Here we describe the synthesis of two imido analogs uranyl ion, UO(2+)2, in which oxygens are replaced by divalent alkyl or aryl nitrogen groups: U(NtBu)2I2(THF)2 (1) and U(NPh)2I2(THF)3 (2) (where tBu is tert-butyl THF tetrahydrofuran). Both compounds have been fully characterized standard analytical techniques, including x-ray crystallography, chemical bonding between metal center ligands was quantified using hybrid density functional theory calculations. As expected for a analog, these...
Two mononuclear high-spin Fe(II) complexes with trigonal planar ([Fe(II)(N(TMS)(2))(2)(PCy(3))] (1) and distorted tetrahedral ([Fe(II)(N(TMS)(2))(2)(depe)] (2) geometries are reported (TMS = SiMe(3), Cy cyclohexyl, depe 1,2-bis(diethylphosphino)ethane). The magnetic properties of 1 2 reveal the profound effect out-of-state spin-orbit coupling (SOC) on slow relaxation. Complex exhibits relaxation magnetization under an applied optimal dc field 600 Oe due to presence low-lying electronic...
Ammonia-borane (NH(3)BH(3), AB) has garnered interest as a hydrogen storage material due to its high weight percent content and ease of H(2) release relative metal hydrides. As consequence dehydrogenation, B-N-containing oligomeric/polymeric materials are formed. The ability control this process dictate the identity generated polymer opens up possibility targeted synthesis new materials. While precious metals have been used in regard, construct such using earth-abundant Fe presents more...
Reaction of (C5Me5)2U(=N-2,4,6-(t)Bu3-C6H2) or (C5Me5)2U(=N-2,6-(i)Pr2-C6H3)(THF) with 5 equiv CuX(n) (n = 1, X Cl, Br, I; n 2, F) affords the corresponding uranium(V)-imido halide complexes, (C5Me5)2U(=N-Ar)(X) (where Ar 2,4,6-(t)Bu3-C6H2 and F (3), Cl (4), Br (5), I (6); 2,6-(i)Pr2-C6H3 (7), (8), (9), (10)), in good isolated yields 75-89%. These compounds have been characterized by a combination single-crystal X-ray diffraction, (1)H NMR spectroscopy, elemental analysis, mass spectrometry,...
Treatment of M[N(SiMe3)2]3 (M = U, Pu (An); La, Ce (Ln)) with NH(EPPh2)2 and NH(EPiPr2)2 (E S, Se), afforded the neutral complexes M[N(EPR2)2]3 (R Ph, iPr). Tellurium donor were synthesized by treatment MI3(sol)4 Pu; sol py M Ce; thf) Na(tmeda)[N(TePiPr2)2]. The have been structurally spectroscopically characterized concomitant computational modeling through density functional theory (DFT) calculations. An−E bond lengths are shorter than Ln−E for metal ions similar ionic radii, consistent an...
Dipicolinate vanadium(V) complexes oxidize lignin model pinacol monomethyl ether (A), 2-phenoxyethanol (B), 1-phenyl-2-phenoxyethanol (C), and 1,2-diphenyl-2-methoxyethanol (D). With substrates having C−H bonds adjacent to the alcohol moiety (B−D), bond is broken in pyridine-d5 solvent, yielding 2-phenoxyacetaldehyde from B, 2-phenoxyacetophenone C, benzoin methyl D. In DMSO-d6 solvent reaction slower, both C−C cleavage products are observed for The vanadium(IV) of these reactions have been...
The fused-ring heterocycle 4-amino-3,7,8-trinitropyrazolo-[5,1-<italic>c</italic>][1,2,4]triazine (PTX) has promising explosive properties.
We report the synthesis and physical properties of single crystals stoichiometric BaNi2As2 that crystalizes in ThCr2Si2 structure with lattice parameters a = 4.112(4) Åand c 11.54(2) Å. Resistivity heat capacity show first order phase transition at T_0 130 K thermal hysteresis 7 K. The Hall coefficient is weakly temperature dependent from room to 2 where it has value -4x10^{-10} Ω-cm/Oe. Resistivity, ac-susceptibility, find evidence for bulk superconductivity T_c 0.7 Sommerfeld 11.6 \pm 0.9...
Understanding the bonding trends within, and differences between, 4f 5f element series with soft donor atom ligands will aid elucidation of fundamental origins actinide (An) versus lanthanide (Ln) selectivity that is integral to many advanced nuclear fuel cycle separation concepts. One principal obstacles acquiring such knowledge dearth well characterized transuranic molecules prevents necessary comparison coordination chemistry, electronic structure, bonding. Reported herein new chemistry...
The first lanthanide complex featuring a phosphinidene functional group has been prepared and isolated. Preliminary reactivity studies demonstrate that the lutetium(III) complex, [{2-(iPr2P)-4-Me-C6H3}2NLu]2(μ-PMes)2, behaves as phospha-Wittig reagent with aldehydes ketones to give corresponding phosphaalkenes. Attempts use bulky phosphine H2P-2,4,6-tBu3-C6H2 kinetically stabilize terminal resulted in C−H activation of an ortho-tBu formation phosphaindole.