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Sebastian Fichter Sebastian Kaufmann Dr. Peter Kaden Dr. Tobias S. Brunner Prof. Dr. Thorsten Stumpf Prof. Dr. Peter W. Roesky Dr. Juliane März 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(41):8867-8870
The synthesis of a tetravalent neptunium amidinate [NpCl((S)-PEBA)3] ( 1 ) ((S)-PEBA=(S,S)-N,N′-bis-(1-phenylethyl)-benzamidinate) is reported. This complex represents the first structurally characterized enantiopure transuranic compound. Reactivity studies with halide/pseudohalides yielding [NpX((S)-PEBA)3] (X=F ( 2 ), Br ( 3 ), N3 ( 4 )) have shown that the chirality-at-metal is preserved for all compounds in the solid state. Furthermore, they represent an unprecedented example of a structurally characterized metal–organic Np complex featuring a Np−Br ( 3 ) bond. In addition, 4 is the only reported tetravalent transuranic azide. All compounds were additionally characterized in solution using para-magnetic NMR spectroscopy showing an expected C3-symmetry at low temperatures. 相似文献
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ChemInform Abstract: Structure,Properties, and Theoretical Electronic Structure of UCuOP and NpCuOP.
Daniel M. Wells Emilie Ringe D. Kaczorowski D. Gnida G. Andre Richard G. Haire Donald E. Ellis James A. Ibers 《ChemInform》2011,42(13):no-no
The title compounds are prepared by solid state reaction of U or Np, Cu and/or CuO, and P at 1073—1273 K (evacuated silica tube, 96 h). 相似文献
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F. Rösch Tran Kim Hung S. Dittrich R. Ludwig G. V. Buklanov R. Dreyer 《Isotopes in environmental and health studies》2013,49(8):355-363
Ion mobilities of carrier-free 239Np(V) have been measured in aqueous solutions, T = 298.1 (1) K. Ion mobilities of 239NpO2 + and its dependencies on pH of acidic inert electrolytes have been measured. In alkaline solutions the stoichimetric hydrolysis constants of NpO2(OH) as well as NpO2(OH)2 ? have been obtained. Complex formations of 239Np(V) with oxalate, tartrate, sulphate, acetate and citrate ligands have been studied in neutral solutions. 相似文献
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Dr. Korey P. Carter Dr. Kurt F. Smith Toni Tratnjek Katherine M. Shield Dr. Liane M. Moreau Dr. Julian A. Rees Dr. Corwin H. Booth Prof. Dr. Rebecca J. Abergel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(11):2354-2359
Octadentate hydroxypyridinone (HOPO) and catecholamide (CAM) siderophore analogues are known to be efficacious chelators of the actinide cations, and these ligands are also capable of facilitating both activation and reduction of actinyl species. Utilizing X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopies, as well as cyclic voltammetry measurements, herein, we elucidate chelation-based mechanisms for driving reactivity and initiating redox processes in a family of neptunyl–HOPO and CAM complexes. Based on the selected chelator, the ability to control the oxidation state of neptunium and the speed of reduction and concurrent oxo group activation was demonstrated. Most notably, reduction kinetics for the NpVO2+//NpIV redox couple upon chelation by the ligands 3,4,3-LI(1,2-HOPO) and 3,4,3-LI(CAM)2(1,2-HOPO)2 was observed to be faster than ever reported, and in fact quicker than we could measure using either X-ray absorption spectroscopy or electrochemical techniques. 相似文献
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Dr. Evan L. Thomas Samantha Stegman Dr. Suntharalingam Skanthakumar Dr. Richard E. Wilson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(7):1497-1500
Hydrofluxes are hydrated salts with melting points well below that of the dehydrated salt and boiling points well above that of water, affording a reaction medium, in which mild temperatures and pressures can be accessed for the synthesis of materials. Herein, the use of alkali metal hydroxide hydrofluxes for the synthesis of single crystal α-Na2NpO4 is described, and the single crystal X-ray structure of α-Na2NpO4, along with its X-ray absorption spectra and vibrational spectra, is reported. The ability to synthesize complex oxides of the actinides, in particular, transuranium materials, under mild conditions will serve to advance our ability to explore the structure–property relationships of the f elements. 相似文献
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Subtle Interactions and Electron Transfer between UIII,NpIII, or PuIII and Uranyl Mediated by the Oxo Group 下载免费PDF全文
Prof. Polly L. Arnold Michał S. Dutkiewicz Dr. Markus Zegke Dr. Olaf Walter Dr. Christos Apostolidis Dr. Emmalina Hollis Dr. Anne‐Fréderique Pécharman Dr. Nicola Magnani Dr. Jean‐Christophe Griveau Dr. Eric Colineau Prof. Roberto Caciuffo Xiaobin Zhang Prof. Georg Schreckenbach Prof. Jason B. Love 《Angewandte Chemie (International ed. in English)》2016,55(41):12797-12801
A dramatic difference in the ability of the reducing AnIII center in AnCp3 (An=U, Np, Pu; Cp=C5H5) to oxo‐bind and reduce the uranyl(VI) dication in the complex [(UO2)(THF)(H2L)] (L=“Pacman” Schiff‐base polypyrrolic macrocycle), is found and explained. These are the first selective functionalizations of the uranyl oxo by another actinide cation. At‐first contradictory electronic structural data are explained by combining theory and experiment. Complete one‐electron transfer from Cp3U forms the UIV‐uranyl(V) compound that behaves as a UV‐localized single molecule magnet below 4 K. The extent of reduction by the Cp3Np group upon oxo‐coordination is much less, with a NpIII‐uranyl(VI) dative bond assigned. Solution NMR and NIR spectroscopy suggest NpIVUV but single‐crystal X‐ray diffraction and SQUID magnetometry suggest a NpIII‐UVI assignment. DFT‐calculated Hirshfeld charge and spin density analyses suggest half an electron has transferred, and these explain the strongly shifted NMR spectra by spin density contributions at the hydrogen nuclei. The PuIII–UVI interaction is too weak to be observed in THF solvent, in agreement with calculated predictions. 相似文献
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Maite Garcia‐Hernandez Christa Willnauer Sven Krueger Lyudmila V. Moskaleva Notker Roesch 《ChemInform》2006,37(14):no-no
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. 相似文献