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Nature Chemistry

Qipeng Lu, An-Liang Wang, Yue Gong, Wei Hao, Hongfei Cheng, Junze Chen, Bing Li, Nailiang Yang, Wenxin Niu, Jie Wang, Yifu Yu, Xiao Zhang, Ye Chen, Zhanxi Fan, Xue-Jun Wu, Jinping Chen, Jun Luo, Shuzhou Li, Lin Gu, Hua Zhang
Crystal-phase engineering offers opportunities for the rational design and synthesis of noble metal nanomaterials with unusual crystal phases that normally do not exist in bulk materials. However, it remains a challenge to use these materials as seeds to construct heterometallic nanostructures with desired crystal phases and morphologies for promising applications such as catalysis. Here, we report a strategy for the synthesis of binary and ternary hybrid noble metal nanostructures. Our synthesized crystal-phase heterostructured 4H/fcc Au nanowires enable the epitaxial growth of Ru nanorods on the 4H phase and fcc-twin boundary in Au nanowires, resulting in hybrid Au-Ru nanowires...
March 12, 2018: Nature Chemistry
Mohan Chen, Lixin Zheng, Biswajit Santra, Hsin-Yu Ko, Robert A DiStasio, Michael L Klein, Roberto Car, Xifan Wu
Proton transfer via hydronium and hydroxide ions in water is ubiquitous. It underlies acid-base chemistry, certain enzyme reactions, and even infection by the flu. Despite two centuries of investigation, the mechanism underlying why hydroxide diffuses slower than hydronium in water is still not well understood. Herein, we employ state-of-the-art density-functional-theory-based molecular dynamics-with corrections for non-local van der Waals interactions, and self-interaction in the electronic ground state-to model water and hydrated water ions...
March 12, 2018: Nature Chemistry
Rebecca P Chen, Daniel Blackstock, Qing Sun, Wilfred Chen
Inspired by the remarkable ability of natural protein switches to sense and respond to a wide range of environmental queues, here we report a strategy to engineer synthetic protein switches by using DNA strand displacement to dynamically organize proteins with highly diverse and complex logic gate architectures. We show that DNA strand displacement can be used to dynamically control the spatial proximity and the corresponding fluorescence resonance energy transfer between two fluorescent proteins. Performing Boolean logic operations enabled the explicit control of protein proximity using multi-input, reversible and amplification architectures...
March 12, 2018: Nature Chemistry
Ji Chen, Angelos Michaelides
No abstract text is available yet for this article.
March 12, 2018: Nature Chemistry
Zhen Chen, Phillip A Lichtor, Adrian P Berliner, Jonathan C Chen, David R Liu
The evolution of sequence-defined synthetic polymers made of building blocks beyond those compatible with polymerase enzymes or the ribosome has the potential to generate new classes of receptors, catalysts and materials. Here we describe a ligase-mediated DNA-templated polymerization and in vitro selection system to evolve highly functionalized nucleic acid polymers (HFNAPs) made from 32 building blocks that contain eight chemically diverse side chains on a DNA backbone. Through iterated cycles of polymer translation, selection and reverse translation, we discovered HFNAPs that bind proprotein convertase subtilisin/kexin type 9 (PCSK9) and interleukin-6, two protein targets implicated in human diseases...
March 5, 2018: Nature Chemistry
Finlay Walton, Klaas Wynne
Control over the nucleation of new phases is highly desirable but elusive. Even though there is a long history of crystallization engineering by varying physicochemical parameters, controlling which polymorph crystallizes or whether a molecule crystallizes or forms an amorphous precipitate is still a poorly understood practice. Although there are now numerous examples of control using laser-induced nucleation, the absence of physical understanding is preventing progress. Here we show that the proximity of a liquid-liquid critical point or the corresponding binodal line can be used by a laser-tweezing potential to induce concentration gradients...
March 5, 2018: Nature Chemistry
Gabriel Isaacman-VanWertz, Paola Massoli, Rachel O'Brien, Christopher Lim, Jonathan P Franklin, Joshua A Moss, James F Hunter, John B Nowak, Manjula R Canagaratna, Pawel K Misztal, Caleb Arata, Joseph R Roscioli, Scott T Herndon, Timothy B Onasch, Andrew T Lambe, John T Jayne, Luping Su, Daniel A Knopf, Allen H Goldstein, Douglas R Worsnop, Jesse H Kroll
The evolution of atmospheric organic carbon as it undergoes oxidation has a controlling influence on concentrations of key atmospheric species, including particulate matter, ozone and oxidants. However, full characterization of organic carbon over hours to days of atmospheric processing has been stymied by its extreme chemical complexity. Here we study the multigenerational oxidation of α-pinene in the laboratory, characterizing products with several state-of-the-art analytical techniques. Although quantification of some early generation products remains elusive, full carbon closure is achieved (within measurement uncertainty) by the end of the experiments...
February 26, 2018: Nature Chemistry
Pranav R Shirhatti, Igor Rahinov, Kai Golibrzuch, Jörn Werdecker, Jan Geweke, Jan Altschäffel, Sumit Kumar, Daniel J Auerbach, Christof Bartels, Alec M Wodtke
The most common mechanism of catalytic surface chemistry is that of Langmuir and Hinshelwood (LH). In the LH mechanism, reactants adsorb, become thermalized with the surface, and subsequently react. The measured vibrational (relaxation) lifetimes of molecules adsorbed at metal surfaces are in the range of a few picoseconds. As a consequence, vibrational promotion of LH chemistry is rarely observed, with the exception of LH reactions occurring via a molecular physisorbed intermediate. Here, we directly detect adsorption and subsequent desorption of vibrationally excited CO molecules from a Au(111) surface...
February 26, 2018: Nature Chemistry
Zhi Gao, Tijs Karman, Sjoerd N Vogels, Matthieu Besemer, Ad van der Avoird, Gerrit C Groenenboom, Sebastiaan Y T van de Meerakker
Although collisions between atoms and molecules are largely understood, collisions between two molecules have proven much harder to study. In both experiment and theory, our ability to determine quantum-state-resolved bimolecular cross-sections lags behind their atom-molecule counterparts by decades. For many bimolecular systems, even rules of thumb-much less intuitive understanding-of scattering cross sections are lacking. Here, we report the measurement of state-to-state differential cross sections on the collision of state-selected and velocity-controlled nitric oxide (NO) radicals and oxygen (O2 ) molecules...
February 19, 2018: Nature Chemistry
Sjoerd N Vogels, Tijs Karman, Jacek Kłos, Matthieu Besemer, Jolijn Onvlee, Ad van der Avoird, Gerrit C Groenenboom, Sebastiaan Y T van de Meerakker
Over the last 25 years, the formalism known as coupled-cluster (CC) theory has emerged as the method of choice for the ab initio calculation of intermolecular interaction potentials. The implementation known as CCSD(T) is often referred to as the gold standard in quantum chemistry. It gives excellent agreement with experimental observations for a variety of energy-transfer processes in molecular collisions, and it is used to calibrate density functional theory. Here, we present measurements of low-energy collisions between NO radicals and H2 molecules with a resolution that challenges the most sophisticated quantum chemistry calculations at the CCSD(T) level...
February 19, 2018: Nature Chemistry
Daniel G Kohler, Samuel N Gockel, Jennifer L Kennemur, Peter J Waller, Kami L Hull
In recent years, the synthesis of amines and other nitrogen-containing motifs has been a major area of research in organic chemistry because they are widely represented in biologically active molecules. Current strategies rely on a multistep approach and require one reactant to be activated prior to the carbon-nitrogen bond formation. This leads to a reaction inefficiency and functional group intolerance. As such, a general approach to the synthesis of nitrogen-containing compounds from readily available and benign starting materials is highly desirable...
March 2018: Nature Chemistry
Urmimala Maitra, Robert A House, James W Somerville, Nuria Tapia-Ruiz, Juan G Lozano, Niccoló Guerrini, Rong Hao, Kun Luo, Liyu Jin, Miguel A Pérez-Osorio, Felix Massel, David M Pickup, Silvia Ramos, Xingye Lu, Daniel E McNally, Alan V Chadwick, Feliciano Giustino, Thorsten Schmitt, Laurent C Duda, Matthew R Roberts, Peter G Bruce
The search for improved energy-storage materials has revealed Li- and Na-rich intercalation compounds as promising high-capacity cathodes. They exhibit capacities in excess of what would be expected from alkali-ion removal/reinsertion and charge compensation by transition-metal (TM) ions. The additional capacity is provided through charge compensation by oxygen redox chemistry and some oxygen loss. It has been reported previously that oxygen redox occurs in O 2p orbitals that interact with alkali ions in the TM and alkali-ion layers (that is, oxygen redox occurs in compounds containing Li+ -O(2p)-Li+ interactions)...
March 2018: Nature Chemistry
Jani Reddy Bolla, Joshua B Sauer, Di Wu, Shahid Mehmood, Timothy M Allison, Carol V Robinson
Translocation of lipid II across the cytoplasmic membrane is essential in peptidoglycan biogenesis. Although most steps are understood, identifying the lipid II flippase has yielded conflicting results, and the lipid II binding properties of two candidate flippases-MurJ and FtsW-remain largely unknown. Here we apply native mass spectrometry to both proteins and characterize lipid II binding. We observed lower levels of lipid II binding to FtsW compared to MurJ, consistent with MurJ having a higher affinity...
March 2018: Nature Chemistry
Dominik P Halter, Frank W Heinemann, Laurent Maron, Karsten Meyer
The reactivity of uranium compounds towards small molecules typically occurs through stoichiometric rather than catalytic processes. Examples of uranium catalysts reacting with water are particularly scarce, because stable uranyl groups form that preclude the recovery of the uranium compound. Recently, however, an arene-anchored, electron-rich uranium complex has been shown to facilitate the electrocatalytic formation of H2 from H2 O. Here, we present the precise role of uranium-arene δ bonding in intermediates of the catalytic cycle, as well as details of the atypical two-electron oxidative addition of H2 O to the trivalent uranium catalyst...
March 2018: Nature Chemistry
Cameron B Dover, Joseph K Gallaher, Laszlo Frazer, Patrick C Tapping, Anthony J Petty, Maxwell J Crossley, John E Anthony, Tak W Kee, Timothy W Schmidt
Singlet fission is a process whereby two triplet excitons can be produced from one photon, potentially increasing the efficiency of photovoltaic devices. Endothermic singlet fission is desired for a maximum energy-conversion efficiency, and such systems have been considered to form an excimer-like state with multiexcitonic character prior to the appearance of triplets. However, the role of the excimer as an intermediate has, until now, been unclear. Here we show, using 5,12-bis((triisopropylsilyl)ethynyl)tetracene in solution as a prototypical example, that, rather than acting as an intermediate, the excimer serves to trap excited states to the detriment of singlet-fission yield...
March 2018: Nature Chemistry
Joshua P Rogers, Cate S Anstöter, Jan R R Verlet
The primary electron-attachment process in electron-driven chemistry represents one of the most fundamental chemical transformations with wide-ranging importance in science and technology. However, the mechanistic detail of the seemingly simple reaction of an electron and a neutral molecule to form an anion remains poorly understood, particularly at very low electron energies. Here, time-resolved photoelectron imaging was used to probe the electron-attachment process to a non-polar molecule using time-resolved methods...
March 2018: Nature Chemistry
Barry A Badeau, Michael P Comerford, Christopher K Arakawa, Jared A Shadish, Cole A DeForest
The successful transport of drug- and cell-based therapeutics to diseased sites represents a major barrier in the development of clinical therapies. Targeted delivery can be mediated through degradable biomaterial vehicles that utilize disease biomarkers to trigger payload release. Here, we report a modular chemical framework for imparting hydrogels with precise degradative responsiveness by using multiple environmental cues to trigger reactions that operate user-programmable Boolean logic. By specifying the molecular architecture and connectivity of orthogonal stimuli-labile moieties within material cross-linkers, we show selective control over gel dissolution and therapeutic delivery...
March 2018: Nature Chemistry
David L Niquille, Douglas A Hansen, Takahiro Mori, David Fercher, Hajo Kries, Donald Hilvert
Biosynthetic modification of nonribosomal peptide backbones represents a potentially powerful strategy to modulate the structure and properties of an important class of therapeutics. Using a high-throughput assay for catalytic activity, we show here that an L-Phe-specific module of an archetypal nonribosomal peptide synthetase can be reprogrammed to accept and process the backbone-modified amino acid (S)-β-Phe with near-native specificity and efficiency. A co-crystal structure with a non-hydrolysable aminoacyl-AMP analogue reveals the origins of the 40,000-fold α/β-specificity switch, illuminating subtle but precise remodelling of the active site...
March 2018: Nature Chemistry
Yi-Qi Zhang, Mateusz Paszkiewicz, Ping Du, Liding Zhang, Tao Lin, Zhi Chen, Svetlana Klyatskaya, Mario Ruben, Ari P Seitsonen, Johannes V Barth, Florian Klappenberger
Interfacial supramolecular self-assembly represents a powerful tool for constructing regular and quasicrystalline materials. In particular, complex two-dimensional molecular tessellations, such as semi-regular Archimedean tilings with regular polygons, promise unique properties related to their nontrivial structures. However, their formation is challenging, because current methods are largely limited to the direct assembly of precursors, that is, where structure formation relies on molecular interactions without using chemical transformations...
March 2018: Nature Chemistry
B Dicke, A Hoffmann, J Stanek, M S Rampp, B Grimm-Lebsanft, F Biebl, D Rukser, B Maerz, D Göries, M Naumova, M Biednov, G Neuber, A Wetzel, S M Hofmann, P Roedig, A Meents, J Bielecki, J Andreasson, K R Beyerlein, H N Chapman, C Bressler, W Zinth, M Rübhausen, S Herres-Pawlis
The entatic state denotes a distorted coordination geometry of a complex from its typical arrangement that generates an improvement to its function. The entatic-state principle has been observed to apply to copper electron-transfer proteins and it results in a lowering of the reorganization energy of the electron-transfer process. It is thus crucial for a multitude of biochemical processes, but its importance to photoactive complexes is unexplored. Here we study a copper complex-with a specifically designed constraining ligand geometry-that exhibits metal-to-ligand charge-transfer state lifetimes that are very short...
March 2018: Nature Chemistry
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