Article
Chemistry, Multidisciplinary
Wei Fang, Ambre Carpentier, Xiong Sun, Yue Zhao, Laurent Maron, Congqing Zhu
Summary: A synthesized redox-active multidentate N-P ligand reacted with UCl4 in the presence of KHMDS or (BuLi)-Bu-n, forming two novel U(iv) complexes, one with P-P coupling and one without. The reversible P-P coupling in these complexes was observed in redox-induced reactions.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Inorganic & Nuclear
Daniel M. Beagan, Alyssa C. Cabelof, Kenneth G. Caulton
Summary: A density functional theory study explored the influence of ligands on the geometry and back donation to nitrogen oxyanions, revealing the impact of different ligands on nitrate reduction processes. Stronger ligands directly lead to nitrate reduction, while milder ligands require the addition of a Lewis base for nitrate reduction to occur.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Multidisciplinary
Khrystyna Herasymchuk, Magali Allain, Gregory A. MacNeil, Vincent Carre, Frederic Aubriet, Daniel B. Leznoff, Marc Salle, Sebastien Goeb, Tim Storr
Summary: The study explored the incorporation of a redox-active nickel salen complex into supramolecular structures by coordination-driven self-assembly with homobimetallic ruthenium complexes. The formation of a discrete rectangle and either a rectangle or a catenane depended on the solvent and concentration. Analysis through electrochemical experiments, UV-Vis-NIR absorption, EPR spectroscopy, and DFT calculations confirmed ligand radical formation and provided further insights into the geometric and electronic structures in solution.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Leyla R. Valerio, Brett M. Hakey, William W. Brennessel, Ellen M. Matson
Summary: This article provides a detailed description of the reductive silylation of the uranyl dication using 1,4-bis(trimethylsilyl)-dihydropyrazine (or Mashima's reagent). The reaction effectively activates thermodynamically stable U=O bonds, making it a promising solution for nuclear waste remediation.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Lucy E. Darago, Monica D. Boshart, Brian D. Nguyen, Eva Perlt, Joseph W. Ziller, Wayne W. Lukens, Filipp Furche, William J. Evans, Jeffrey R. Long
Summary: Researchers have synthesized and characterized a series of trinuclear 4d-4f compounds with highly polarizable MoS 4 3- bridging units. The compounds exhibit specific metal-to-metal charge transfer properties, significant unpaired electron density, and ferromagnetic exchange behavior, providing a potential route for the design of new nd-4f single-molecule magnets and bulk magnetic materials.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Inorganic & Nuclear
Hai-Jun Li, Rui Feng, Gao-Xiang Wang, Junnian Wei, Zhenfeng Xi
Summary: By reacting semi-rigid PNP ligand with CoBr2, complex PNPCoBr (1) was obtained. The reduction of 1 with excess amounts of KC8 in THE under a N-2 atmosphere yielded binuclear cobalt dinitrogen anion complex [Co(mu-Cy2P)PCyN2](2)K (2) by cleaving the C-P bond of the PNP ligand. Adding 2,2,2-cryptand into complex 2 effectively prepared ion pair Co complex, [Co(mu-Cy2P)PCyN2](2)K(crypt-222) (3). The structures of 1, 2, and 3 were determined by single-crystal X-ray diffraction analysis, and N-2 is moderately activated in complexes 2 and 3. DFT calculations suggest the presence of a Co-Co bond in 2 and 3. Compounds 1 and 2 exhibit catalytic activity for the transformation of N-2 to N(SiMe3)(3).
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Multidisciplinary
Xiaoxiao Wei, Xiaojian Wen, Yingying Liu, Chen Chen, Chao Xie, Dongdong Wang, Mengyi Qiu, Nihan He, Peng Zhou, Wei Chen, Jun Cheng, Hongzhen Lin, Jianfeng Jia, Xian-Zhu Fu, Shuangyin Wang
Summary: This study proposes a new method for synthesizing urea at ambient conditions, which improves the efficiency of the C-N coupling reaction by stabilizing the crucial intermediate through the insertion of oxygen vacancies. The existence of oxygen vacancy-mediated selective C-N coupling reaction is verified through in situ spectroscopy techniques. The introduction of oxygen vacancies transforms the common catalyst carrier into an efficient electrocatalyst, with a higher urea yield rate compared to partial noble-metal-based electrocatalysts.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Biochemical Research Methods
Qi Huang, Monika Tokmina-Lukaszewska, Lewis E. Johnson, Hayden Kallas, Bojana Ginovska, John W. Peters, Lance C. Seefeldt, Brian Bothner, Simone Raugei
Summary: The nitrogenase complex shows hierarchical complexity through long-range mechanical coupling for communication between distant regions, facilitating the regulation of nitrogen reduction. Large-scale correlated motions near active sites enable inter- and intra-half communications within the complex, with specific regions like the P-loops and switch regions playing crucial roles. This study provides valuable insights into the important regions and mechanisms of communication within the nitrogenase complex, contributing to future mechanistic studies.
PLOS COMPUTATIONAL BIOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Wolfgang Leis, Miguel A. Arguello Cordero, Stefan Lochbrunner, Hartmut Schubert, Andreas Berkefeld
Summary: Controlling the order and lifetimes of electronically excited states is crucial for efficient light-to-potential energy conversion. This study presents a luminescent and photoreactive iron(II) complex, which is the first high-performance analogue of prototypical ruthenium sensitizers. The double cyclometalation of a phenylphenanthroline framework at iron(II) promotes the formation of a triplet metal-to-ligand charge transfer ((MLCT)-M-3) state as the lowest energy excited state. Near-infrared (NIR) luminescence exhibits a monoexponential decay with a lifetime of 2.4 ns in the solid state and 1 ns in the liquid phase. At 77 K, the lifetime extends to 14 ns, accompanied by a narrowing of the NIR emission band within the range of 1170-1230 nm. The Fe(II) chromophore, featuring a (MLCT)-M-3 excited-state redox potential of -2 V vs the ferrocene/ferrocenium couple, is demonstrated to be a sensitizer for light-driven synthesis through the radical cross-coupling of 4-chlorobromobenzene and benzene.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Organic
Dawei Gong, Degong Kong, Na Xu, Yuhui Hua, Bo Liu, Zhanlin Xu
Summary: A new method for the synthesis of hydrazoarenes is developed by using ethanol as a hydrogen source and a bidentate Ru(II)-NC complex as the catalyst. The presence of a weak base is crucial for efficient semihydrogenation, which prevents hydrazoarene dehydrogenation under strongly basic conditions. Control experiments and density functional theory calculations confirm the mechanism as Meerwein-Ponndorf-Verley mechanism, with ethyl acetate as the only byproduct. This study offers a new and simple approach for the synthesis of hydrazoarenes.
Article
Chemistry, Multidisciplinary
Shuo Chen, Yanyan Ma, Liang Zhang, Yuanyuan Zhang, Yuehui Chen, Xiaohua Zhang, Jianhua Yan
Summary: ZrO2 can stabilize Co catalyst through interface electron coupling, enabling efficient oxygen reduction reaction. Additionally, ZrO2 acts as an electron reservoir, solving the issue of easy deactivation of Co.
Article
Chemistry, Inorganic & Nuclear
Brett M. Hakey, Dylan C. Leary, Lauren M. Lopez, Leyla R. Valerio, William W. Brennessel, Carsten Milsmann, Ellen M. Matson
Summary: The first actinide complexes of the pyridine dipyrrolide (PDP) ligand class have been reported, and their chemical properties and structures have been studied. The compounds exhibit rich redox profiles and distorted octahedral geometry.
INORGANIC CHEMISTRY
(2022)
Article
Environmental Sciences
Yijin Yuan, Lizhen Feng, Xianqin He, Mengsi Wu, Zhihui Ai, Lizhi Zhang, Jingming Gong
Summary: This study explored the significantly accelerated defluorination of recalcitrant perfluorooctanoic acid (PFOA) with the co-present nitrate by UV/sulfite treatment. The deep defluorination of PFOA and complete denitrification of nitrate were simultaneously achieved in the UV/sulfite-nitrate system. It was found that reactive nitrogen species (RNS) played significant roles in the promoted defluorination apart from reductive defluorination. The results highlight the importance of the UV/sulfite-nitrate system for the remediation of perfluorinated compound contaminated water.
ENVIRONMENTAL POLLUTION
(2022)
Article
Chemistry, Physical
Wenjie Cui, Baokang Geng, Xiang Chu, Jianing He, Lingxi Jia, Xiaoxiao Han, Xiao Wang, Shuyan Song, Hongjie Zhang
Summary: This study presents a dual-site strategy for boosting the performance of electrochemical nitrogen reduction reaction (NRR), leading to significantly improved efficiency and NH3 yield rate with higher Faradaic efficiency.
Article
Chemistry, Multidisciplinary
Asa W. Nichols, Joseph S. Kuehner, Brittany L. Huffman, Peter R. Miedaner, Diane A. Dickie, Charles W. Machan
Summary: In this study, a Co-based complex was utilized for the reduction of O2 to H2O, showing selectivity for the four-electron/four-proton reduction product. The key selectivity difference was found to arise from increased favorability of protonation at the distal O position of the key intermediate Co(III)-hydroperoxide. Interestingly, no product selectivity dependence was observed with respect to the presence of pyridine during catalysis.
CHEMICAL COMMUNICATIONS
(2021)
Article
Physics, Condensed Matter
G. H. Lander, M. Sundermann, R. Springell, A. C. Walters, A. Nag, M. Garcia-Fernandez, K. J. Zhou, G. van der Laan, R. Caciuffo
Summary: Resonant inelastic x-ray spectroscopy has been used to reveal excitations in UO2 up to 1 eV at the uranium N-4 absorption edge. The study confirms earlier research on crystal-field states within the H-3(4) multiplet and establishes the first excited state of the F-3(2) multiplet. This successful application of soft x-ray spectroscopy to an actinide sample resolves a question in UO2 that has been discussed for 50 years.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Chemistry, Physical
Ryan W. F. Kerr, Paul M. D. A. Ewing, Sumesh K. Raman, Andrew D. Smith, Charlotte K. Williams, Polly L. Arnold
Summary: Homogeneous Ce(III)-N-heterocyclic carbene (NHC) catalysts exhibit outstanding activities and selectivity in producing cyclic polyesters. By combining cerium(III) and N-heterocyclic carbene functionalities, high molar mass cyclic polylactide can be efficiently produced.
Article
Chemistry, Inorganic & Nuclear
Polly L. Arnold, Connor J. Halliday, Laura Puig-Urrea, Gary S. Nichol
Summary: The unexpected spontaneous reactions between electropositive actinide cations and neutral arenes such as benzene result in the formation of inverse arene sandwich (IAS) complexes, shedding light on the anomalous spectra and reported lack of reactivity of the U-III centers. Phosphines, which are not typically considered suitable ligands for actinides, can catalyze the formation of these complexes, allowing for isolated asymmetric and less congested IAS complexes to be studied for bonding comparisons.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Inorganic & Nuclear
Steven J. Gray, Karen Brown, Francis Y. T. Lam, Jennifer A. Garden, Polly L. Arnold
Summary: A library of new dinuclear Ce-IV complexes with tetraphenolate ligands exhibit excellent catalytic activity for ring-opening copolymerization, providing high turnover frequencies, low dispersities, and tunable rates due to the closely coupled di-Ce-IV unit. Rare-earth complexes as ROCOP initiators deserve further attention.
Article
Chemistry, Multidisciplinary
Michal S. Dutkiewicz, Conrad A. P. Goodwin, Mauro Perfetti, Andrew J. Gaunt, Jean-Christophe Griveau, Eric Colineau, Attila Kovacs, Ashley J. Wooles, Roberto Caciuffo, Olaf Walter, Stephen T. Liddle
Summary: Neptunium, the first artificially synthesized actinide, has been less studied compared to its famous neighbors uranium and plutonium. This study reports the synthesis, isolation, and characterization of a stable molecular neptunium(V)-mono(oxo) triamidoamine complex, demonstrating the possibility of stabilizing and studying high-oxidation-state transuranic complexes with a single metal-ligand bond.
Article
Chemistry, Inorganic & Nuclear
Francis Y. T. Lam, Jordann A. L. Wells, Tatsumi Ochiai, Connor J. Halliday, Karl N. McCabe, Laurent Maron, Polly L. Arnold
Summary: This article uses modular tetraphenolate ligands tethered with a protective arene platform to support mononuclear An(IV) complexes and investigates their interactions and electronic structures with the arene. The study also explores the potential of these complexes as molecular qubits.
INORGANIC CHEMISTRY
(2022)
Article
Multidisciplinary Sciences
Amy N. Price, Victoria Berryman, Tatsumi Ochiai, Jacob J. Shephard, Simon Parsons, Nikolas Kaltsoyannis, Polly L. Arnold
Summary: The article explores whether low-coordinate f-block molecules become more planar or pyramidal under pressure using high-pressure crystallography, with the result being dictated by the dipole moment of the complex and the volume of the planar form.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Jacob J. Shephard, Victoria E. J. Berryman, Tatsumi Ochiai, Olaf Walter, Amy N. Price, Mark R. Warren, Polly L. Arnold, Nikolas Kaltsoyannis, Simon Parsons
Summary: The study shows that pressure can distort actinide-oxygen bonding, and the effects vary for different actinide elements due to their atomic size. Electronic structure calculations reveal that the increased contributions of metal 6d and 5f orbitals to the metal-oxygen bonding result in the shortening of these bonds and enhance the flexibility of MO4 cores.
NATURE COMMUNICATIONS
(2022)
Review
Physics, Multidisciplinary
R. Caciuffo, G. H. Lander, G. van der Laan
Summary: Research on actinide materials has been greatly advanced by the general techniques available from high-intensity photon beams from x-ray synchrotron sources, which can work with minute samples and reduce the radioactive hazards. The article discusses the form and encapsulation procedures used for different techniques and presents the basic theory for interpreting the results. It also reviews a selection of experiments to demonstrate the potential of synchrotron radiation techniques for studying actinide materials.
REVIEWS OF MODERN PHYSICS
(2023)
Article
Chemistry, Inorganic & Nuclear
Amy N. Price, Ankur K. Gupta, Wibe A. de Jong, Polly L. Arnold
Summary: The chemistry of the tris-carbene anion phenyltris(3-alkyl-imidazoline-2-yliden-1-yl)borate, [C3(Me)](-) ligand, for f-block metal cations was investigated. Neutral, molecular complexes were formed for cerium(iii), while a separated ion pair was formed for ytterbium(iii). Computational analyses demonstrated the stronger s donation and greater covalency in the metal-carbon bonds of the [C3(Me)](-) complexes compared to the Tp(Me,Me) complexes. DFT calculations confirmed the crucial role of THF solvent in accurately reproducing the observed molecular and ion-pair geometries for the Ce and Yb complexes.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Amy E. Kynman, Stella Christodoulou, Erik T. Ouellette, Appie Peterson, Sheridon N. Kelly, Laurent Maron, Polly Arnold
Summary: Simple lanthanide cyclopentadienyl (Cp) complexes can photochemically cleave the sp3 carbon-chlorine bond of unactivated chlorinated hydrocarbons including polyvinyl chloride (PVC). The long excited state lifetimes and efficient light absorption by the Cp ligand enhance the photocatalytic reactivity of cerium complexes and enable light reactivity for neighboring lanthanide congeners.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Amy E. Kynman, Luca K. Elghanayan, Addison N. Desnoyer, Yan Yang, Laurent Severy, Andrea Di Giuseppe, T. Don Tilley, Laurent Maron, Polly L. Arnold
Summary: The controlled functionalization of a single fluorine in a CF3 group is difficult and rare. This study demonstrates the importance of metal-ligand cooperativity in organometallic photocatalysis.
Article
Materials Science, Multidisciplinary
Luigi Paolasini, Daniel Chaney, Alexei Bosak, Gerard H. Lander, Roberto Caciuffo
Summary: Despite many years of research, the full complexity of the electron-lattice interactions in UO2 is not fully understood. X-ray inelastic scattering at low temperature reveals that the interaction between electronic degrees of freedom and transverse acoustic phonons is strong only along the reciprocal space direction [100]. The anisotropy in phonon-linewidth broadening leads to an anisotropy in thermal conductivity, which is observed even above the Neel temperature, but cannot be explained with existing models for a cubic material.
Article
Chemistry, Multidisciplinary
Joseph F. DeJesus, Ryan W. F. Kerr, Deborah A. Penchoff, Xian B. Carroll, Charles C. Peterson, Polly L. Arnold, David M. Jenkins
Summary: Highly symmetrical thorium and uranium octakis-carbene 'sandwich' complexes have been prepared by sandwiching the An(IV) cations between two anionic macrocyclic tetra-NHC ligands of different sizes. X-ray crystallography confirmed that the geometry of the metal center can be determined by the size of the macrocyclic ring, leading to different shapes, while DFT calculations revealed that the NHC ligands predominantly exhibit sigma-donation to the metal without pi-backbonding.
Article
Chemistry, Multidisciplinary
Stephanie A. Beach, Jesse L. Guillet, Sydney P. Lagueux, Mauro Perfetti, Brooke N. Livesay, Matthew P. Shores, Jeffrey W. Bacon, Arnold L. Rheingold, Polly L. Arnold, Linda H. Doerrer
CHEMICAL COMMUNICATIONS
(2020)
