Physical chemistry

  • Article
    | Open Access

    The small proton-coupled transporter EmrE confers multidrug resistance in bacteria. The structure of drug-bound EmrE in phospholipid bilayers is now determined using solid-state NMR. The structure provides detailed insights into the molecular mechanism of substrate recognition by this transporter.

    • Alexander A. Shcherbakov
    • , Grant Hisao
    •  & Mei Hong
  • Article
    | Open Access

    Chemical interaction between metal and oxide supports is an important molecular-level factor that influences the catalytic selectivity of a desirable reaction. Here, using Pt nanowires/TiO2 catalytic nanodiodes, the authors investigate an enhancement of both selectivity and hot electron generation on metal-oxide interfacial sites.

    • Si Woo Lee
    • , Jong Min Kim
    •  & Jeong Young Park
  • Article
    | Open Access

    Gas bubbles forming on the surface of an electrode, a phenomenon common to several industrial electrolytic processes, are usually perceived as inert, passivating entities. Here, the authors show that that this general assumption does not hold for gas bubbles masking anodes operating in water.

    • Yan B. Vogel
    • , Cameron W. Evans
    •  & Simone Ciampi
  • Article
    | Open Access

    Controlling and modulating charge transfer dynamics in composite nanostructures, though promising for optoelectronic applications, remains a challenge. Here, the authors report optical control of charge separation and recombination processes in organic semiconductor-based composite nanostructures.

    • Kwang Jin Lee
    • , Elke Beyreuther
    •  & Pascal André
  • Article
    | Open Access

    Porous materials acting as molecular sieves for propylene/propane separation are important for the petrochemical industry. Here the authors show an example of how specific guest-host interactions can result in structural changes in the porous host and shut down diffusion of one of the two similar guest molecules.

    • Dmytro Antypov
    • , Aleksander Shkurenko
    •  & Matthew S. Dyer
  • Article
    | Open Access

    Chemical elements at high pressure may behave more consistently with their periodic properties than they do at ambient conditions. The authors report the synthesis of PH3 from black phosphorous and hydrogen, and the crystallization of the van der Waals compound (PH3)2H2 which fills a gap in the chemistry of adjacent elements in the periodic table.

    • Matteo Ceppatelli
    • , Demetrio Scelta
    •  & Maurizio Peruzzini
  • Article
    | Open Access

    The green component of the solar spectrum can efficiently drive natural photosynthesis, but the process has been little investigated due to the complexity of the excited states involved. Here the authors utilize polarization-dependent two-dimensional electronic-vibrational spectroscopy to define the origin and dynamics of these states in light-harvesting complex II.

    • Eric A. Arsenault
    • , Yusuke Yoneda
    •  & Graham R. Fleming
  • Article
    | Open Access

    Vibrational energy transfer in water involves intermolecular coupling of O-H stretching modes, but much less is known about the role of the bending modes. Here the authors, combining static and femtosecond infrared, Raman, and hyper-Raman spectroscopy and ab initio molecular dynamics simulations, provide insight into the energy dynamics of the bend vibrations.

    • Chun-Chieh Yu
    • , Kuo-Yang Chiang
    •  & Yuki Nagata
  • Article
    | Open Access

    Almost all allosteric systems are large multi-domain proteins which complicates the investigation of the mechanism in atomistic detail. Here authors designed a small allosteric protein system using the photocontrollable PDZ3 domain, that allows controlling allostery between the binding and allosteric site in both directions.

    • Olga Bozovic
    • , Brankica Jankovic
    •  & Peter Hamm
  • Article
    | Open Access

    Molecular understanding of water is challenging due to the structural complexity of liquid water and the large number of ice phases. Here the authors use a machine-learning potential trained on liquid water to demonstrate the structural similarity of liquid water and that of 54 real and hypothetical ice phases.

    • Bartomeu Monserrat
    • , Jan Gerit Brandenburg
    •  & Bingqing Cheng
  • Article
    | Open Access

    Direct observation of carbon dioxide dissociation provides an origin of catalytic conversion for industrial chemical reactions. Here, the authors reveal their molecular interactions on the rhodium catalyst at near-ambient pressure by interface science techniques and computational calculations.

    • Jeongjin Kim
    • , Hyunwoo Ha
    •  & Jeong Young Park
  • Article
    | Open Access

    Understanding the correlation between molecular structure and properties of 2D hybrid perovskites is crucial for material design and device performance. Here, the authors reveal that conformation of organic cations in the inorganic cages has strong effects on charge mobility and broadband emission behaviour.

    • Chuanzhao Li
    • , Jin Yang
    •  & Shuji Ye
  • Article
    | Open Access

    Application of machine-learning approaches to exploring chemical reaction networks is challenging due to need of including open-shell reaction intermediates. Here the authors introduce a density functional theory database of closed and open-shell molecules for machine-learning predictions of reaction energies.

    • Sina Stocker
    • , Gábor Csányi
    •  & Johannes T. Margraf
  • Article
    | Open Access

    Spectroscopic studies of water clusters provide insight into the hydrogen bond structure of water and ice. The authors measure infrared spectra of neutral water octamers using a threshold photoionization technique based on a tunable vacuum-UV free electron laser, identifying two cubic isomers in addition to those previously observed.

    • Gang Li
    • , Yang-Yang Zhang
    •  & Ling Jiang
  • Article
    | Open Access

    Wet-dry cycling is thought to have enabled the production of molecular building blocks of life. Here, the authors investigate the impact of dehydration/rehydration on RNA-containing complex coacervates, which are membraneless compartments formed by phase separation of polyelectrolyte solutions.

    • Hadi M. Fares
    • , Alexander E. Marras
    •  & Christine D. Keating
  • Article
    | Open Access

    Water’s hydrogen-bond network is truncated at hydrophobic interfaces and the dynamics of the resulting free OH groups is not well understood. The authors experimentally show that the main vibrational relaxation mechanism for free OH at the air-water interface is a diffusive molecular reorientation, rather than intramolecular energy transfer.

    • Ken-ichi Inoue
    • , Mohammed Ahmed
    •  & Tahei Tahara
  • Article
    | Open Access

    Here, the authors present an approach that enhances the sensitivity of basic 2D biomolecular NMR experiments like NOESY and TOCSY, when carried out in polysaccharides, proteins and nucleic acids. This method combines principles associated to quantum Anti-Zeno Effects and advanced data acquisition methods based on Hadamard multiplexing.

    • Mihajlo Novakovic
    • , Ēriks Kupče
    •  & Lucio Frydman
  • Article
    | Open Access

    Electrification of water upon contact with hydrophobic surfaces is a ubiquitous but poorly understood phenomenon. Here, the authors pinpoint the factors responsible for the excess positive charge carried by water droplets dispensed from hydrophobic capillaries, thereby answering some outstanding questions and raising new ones.

    • Jamilya Nauruzbayeva
    • , Zhonghao Sun
    •  & Himanshu Mishra
  • Article
    | Open Access

    The symmetry of metal ions in inorganic nanofilms can be manipulated by the transfer of optical spin from a chiral light beam. Here the authors present a route to functional manipulation that does not require the application of extreme conditions.

    • Christopher Kelly
    • , Donald A. MacLaren
    •  & Malcolm Kadodwala
  • Article
    | Open Access

    Multivalent ligand-receptor interactions enhance binding selectivity in biological systems, and may be exploited to design synthetic systems. Here the authors demonstrate a multivalent behavior where the ability to bind the target occurs when the receptor density is within a specific range.

    • Meng Liu
    • , Azzurra Apriceno
    •  & Stefano Angioletti-Uberti
  • Article
    | Open Access

    Carbyne, a linear sp-hybridized carbon allotrope, is synthetically inaccessible and its properties are extrapolated from those of defined oligomers. Here the authors analyze weak optical bands in two series of oligoynes and reassess the optical and fundamental gap of carbyne to lower values than previously suggested.

    • Johannes Zirzlmeier
    • , Stephen Schrettl
    •  & Holger Frauenrath
  • Article
    | Open Access

    Heterogenous ice nucleation is a ubiquitous phenomenon, but predicting the ice nucleation ability of a substrate is challenging. Here the authors develop a machine-learning data-driven approach to predict the ice nucleation ability of substrates, which is based on four descriptors related to physical properties of the interface.

    • Martin Fitzner
    • , Philipp Pedevilla
    •  & Angelos Michaelides
  • Perspective
    | Open Access

    Photon-induced charge separation phenomena are at the heart of light-harvesting applications but challenging to be described by quantum mechanical models. Here the authors illustrate the potential of machine-learning approaches towards understanding the fundamental processes governing electronic excitations.

    • Florian Häse
    • , Loïc M. Roch
    •  & Alán Aspuru-Guzik
  • Article
    | Open Access

    Eumelanin protects cells from sun damage and is promising for energy conversion applications, but its structure and excited state dynamics are elusive. Here the authors shed light on both aspects combining selective excitation of UV- and visible-absorbing chromophores with time-resolved infrared spectroscopy.

    • Christopher Grieco
    • , Forrest R. Kohl
    •  & Bern Kohler
  • Article
    | Open Access

    Chirality of nanostructures may be determined by ensemble measurements in solution or on single immobilized nanoparticles, with loss of detail or interference from the substrate. Here the authors demonstrate that circular differential scattering intensity spectra of freely diffusing single nanoparticles provide chiroptical spectra which reflect their intrinsic chirality.

    • Johannes Sachs
    • , Jan-Philipp Günther
    •  & Peer Fischer
  • Article
    | Open Access

    The identification of molecular quantum states becomes challenging with increasing complexity of the molecular level structure. Here, the authors non-destructively identified excited molecular states of the $${{\rm{N}}}_{2}^{+}$$ N 2 + by interfering forces applied to both the molecular ion and to a co-trapped atomic ion.

    • Kaveh Najafian
    • , Ziv Meir
    •  & Stefan Willitsch
  • Article
    | Open Access

    MoS2 nanoparticles catalyze the extraction of heteroatom S in hydrocarbons by adsorption onto S vacancies. Here, the authors show that S vacancy properties are highly site sensitive and that adsorption of thiophene leads to self-generation of a more open double vacancy site.

    • Norberto Salazar
    • , Srinivas Rangarajan
    •  & Jeppe V. Lauritsen
  • Article
    | Open Access

    Photoreceptor UVR8 in plants senses environmental UV levels through 26 structural tryptophan residues, but the role of 18 of them was unknown. The authors show, by experiments and computations, how these form a light-harvesting network that funnels the excitation to the pyramid centers enhancing the light-perception efficiency.

    • Xiankun Li
    • , Haisheng Ren
    •  & Dongping Zhong
  • Article
    | Open Access

    Protein structural dynamics can be studied by time-resolved crystallography (TRC) and ultrafast transient spectroscopic methods. Here, the authors perform electronic and vibrational transient absorption measurements to characterise the full photocycle of Photoactive Yellow Protein (PYP) both in the crystalline and solution state and find that the photocycle kinetics and structural intermediates of PYP deviate in the crystalline state, which must be taken into consideration when planning TRC experiments.

    • Patrick E. Konold
    • , Enis Arik
    •  & Marie Louise Groot
  • Article
    | Open Access

    The change from low-spin hexacoordinated to high-spin pentacoordinated domed form in heam upon ligand detachment and the reverse process underlie the respiratory function. The authors, using femtosecond time-resolved X-ray emission spectroscopy, capture the transient states connecting the two forms in myoglobin-NO upon NO photoinduced detachment.

    • Dominik Kinschel
    • , Camila Bacellar
    •  & Majed Chergui
  • Article
    | Open Access

    Precise control over the energy of atomic metal sites is key to unlocking novel reaction pathways. Here, the authors achieve selective oxygen activation by the isolated copper site on ceria, due to its reduced 3d orbital energy via cerium induced electron withdrawing effect.

    • Liqun Kang
    • , Bolun Wang
    •  & Feng Ryan Wang
  • Article
    | Open Access

    The synthesis of hydrocarbons with attractive electronic structures remains challenging. Here, the authors describe the synthesis and properties of the C70 fragment as-indaceno[3,2,1,8,7,6-ghijklm]terrylene, which exhibits near-infrared (NIR) absorption.

    • Yuki Tanaka
    • , Norihito Fukui
    •  & Hiroshi Shinokubo
  • Article
    | Open Access

    Electron affinity (EA) is a key parameter in determining the chemical behavior of the elements, but challenging to measure for unstable atoms. Here the authors succeed in measuring the EA of astatine, the heaviest naturally occurring halogen, and compare it with predictions from relativistic calculations.

    • David Leimbach
    • , Julia Karls
    •  & Sebastian Rothe
  • Article
    | Open Access

    Formation of peptide bonds in cold gas-phase environments might represent a prebiotic synthesis route of polypeptides. Here, the authors show the formation of up to tetra-peptide species in the collision of He2+ ions, with kinetic energies typical for solar wind ions, with cold β-alanine clusters.

    • Patrick Rousseau
    • , Dariusz G. Piekarski
    •  & Bernd A. Huber
  • Article
    | Open Access

    Zeolites have pore structures that are attractive for shape-selective catalysis and separation, but targeted synthesis is challenging. Here, the authors propose using a 3D-3D topotactic transformation to synthesize targeted zeolites, including some that may be not feasible with conventional methods.

    • Zhehao Huang
    • , Seungwan Seo
    •  & Xiaodong Zou
  • Article
    | Open Access

    Imaging zeolites in catalysis relies on the use of probe molecules or model catalysts. Here the authors show the synergy of a multiscale reaction-diffusion model and structured illumination microscopy to illustrate spatiotemporal evolution of molecules and acid sites in SAPO-34 zeolites in methanol-to-olefins reaction.

    • Mingbin Gao
    • , Hua Li
    •  & Zhongmin Liu
  • Article
    | Open Access

    The geometric phase effect associated with a conical intersection between the ground and first excited electronic state has been predicted in the H3 system below the conical intersection energy. The authors, by a crossed molecular beam technique and quantum dynamic calculations, provide experimental evidence and insight into its origin.

    • Daofu Yuan
    • , Yin Huang
    •  & Xueming Yang
  • Article
    | Open Access

    The mechanisms of formation of the (6-4) photoproducts in DNA damage by sunlight is still debated. Here the authors show, by optical spectroscopies and computations, the details of the formation of a (6-4) photoadduct via the thietane intermediate in a single-stranded DNA oligonucleotide.

    • Luis A. Ortiz-Rodríguez
    • , Christian Reichardt
    •  & Carlos E. Crespo-Hernández
  • Article
    | Open Access

    γ-Al2O3 is widely used in catalytic processes, but understanding its detailed structure remains a challenge. The authors, using two-dimensional solid-state NMR spectroscopy at a high magnetic field, characterize the spatial proximity and connectivity between oxygen species from the bulk to the surface.

    • Qiang Wang
    • , Wenzheng Li
    •  & Feng Deng
  • Article
    | Open Access

    How a catalyst behaves microscopically under reaction conditions, and what kinds of active sites transiently exist on its surface, is still very much a mystery to the scientific community. Here the authors report on in situ observation of a redox active copper catalyst by a combination of in situ imaging and spectroscopy tools.

    • Jing Cao
    • , Ali Rinaldi
    •  & Marc Willinger
  • Article
    | Open Access

    Current models of halogen bonding describe the σ-symmetric component of this interaction but do not contemplate the possibility of π-covalency. Here the authors provide experimental and computational evidence of π-covalency in halogen bonds involving radical cation halogen bond donors.

    • Cameron W. Kellett
    • , Pierre Kennepohl
    •  & Curtis P. Berlinguette
  • Article
    | Open Access

    Analysis of exchange processes is time consuming by two-dimensional exchange NMR spectroscopy. Here the authors demonstrate a single-scan ultrafast Laplace NMR approach based on spatial encoding to measure molecular diffusion, with an increase by a factor six in the sensitivity per unit time.

    • Otto Mankinen
    • , Vladimir V. Zhivonitko
    •  & Ville-Veikko Telkki
  • Article
    | Open Access

    A fundamental and predictive understanding of molecule-surface interactions is challenging to obtain. Here the authors report an experimental technique allowing direct measurement of the scattering matrix, which reports on the coherent evolution of quantum states of a molecule scattering from a surface.

    • Yosef Alkoby
    • , Helen Chadwick
    •  & Gil Alexandrowicz