Physical chemistry

  • Article |

    The crystallization of a racemate on a surface can lead to crystals with a unit cell containing both enantiomers, or to the separation of enantiomers into crystals of single-handedness. This study shows that manganese co-absorbed with a quinone derivative leads to achiral islands, while co-absorption with caesium gives chiral islands.

    • Nasiba Abdurakhmanova
    • , Andrea Floris
    •  & Klaus Kern
  • Article
    | Open Access

    Understanding hydrogen diffusion in metals is a challenge because of limited access to spatial evolution of the concentration profiles. Using time- and spatially resolved optical measurements, Palssonet al. determine the diffusion rate of hydrogen by directly monitoring its transit through a vanadium thin film.

    • Gunnar K. Pálsson
    • , Andreas Bliersbach
    •  & Björgvin Hjörvarsson
  • Article |

    Geometrically frustrated spin systems are a class of statistical mechanical models that have received widespread attention, especially in condensed matter physics. This study experimentally demonstrates a quantum information processor that can simulate the behaviour of such frustrated spin system.

    • Jingfu Zhang
    • , Man-Hong Yung
    •  & Jonathan Baugh
  • Article |

    Thed orbitals of transition metal compounds influence their crystallographic and physical properties. This study reports a unique structural transition in single crystals of the S=1/2 kagomé antiferromagnet, volborthite, whereby an unpaired electron 'switches' from one dorbital to another upon cooling.

    • Hiroyuki Yoshida
    • , Jun-ichi Yamaura
    •  & Zenji Hiroi
  • Article
    | Open Access

    Prenucleation clusters have been observed during the early stages of calcium carbonate formation, contrary to classical models. Here, computer simulations indicate that the clusters are composed of an ionic polymer with alternating calcium and carbonate ions, and a dynamic topology of chains, branches and rings.

    • Raffaella Demichelis
    • , Paolo Raiteri
    •  & Denis Gebauer
  • Article |

    Dissociation of ice into an ionic solid is rare due to the high energy cost of proton transfer. In this study, structure search simulation is used to predict the formation of a partially ionic phase in ice at low temperature and high pressure, which consists of coupled alternate layers of hydroxide and hydronium.

    • Yanchao Wang
    • , Hanyu Liu
    •  & Yanming Ma
  • Article
    | Open Access

    External electric fields have been used to control the motion of small objects through electrostatic repulsion. Here, electric fields are used to polarize conducting objects, triggering their movement by spatially separated electrochemical reactions leading to directionally controlled bubble evolution.

    • Gabriel Loget
    •  & Alexander Kuhn
  • Article |

    Advanced rechargeable lithium-ion batteries have potential applications in the renewable energy and sustainable road transport fields. Junget al. have developed a lithium battery that uses pre-existing concepts but has highly competitive energy densities, life span and cycling properties.

    • Hun-Gi Jung
    • , Min Woo Jang
    •  & Bruno Scrosati
  • Article |

    Graphene may be used in nanoscale electronics and devices, but the ability to synthesise uniform graphene with well-controlled layer numbers is necessary for these applications. Using a Ni–Mo alloy, this study demonstrates single-layer graphene growth with 100% surface coverage and tolerance to variations in growth conditions.

    • Boya Dai
    • , Lei Fu
    •  & Zhongfan Liu
  • Article |

    Intercalating alkali metals into picene—a hydrocarbon with five linearly fused benzene rings—results in superconducting materials. Now, alkali-metal-doped phenanthrene, which consists of three fused benzene rings, is also found to be superconducting, opening up a broader class of organic superconductors.

    • X.F. Wang
    • , R.H. Liu
    •  & X.H. Chen
  • Article
    | Open Access

    Spin ices are magnetic materials in which excitations equivalent to monopoles can occur. Using high-pressure techniques, Zhouet al. synthesize a new member of the spin ice family, Dy2Ge2O7, in which monopoles exist at higher densities, and can stabilize as dimers.

    • H.D. Zhou
    • , S.T. Bramwell
    •  & J.S. Gardner
  • Article
    | Open Access

    Transparent conducting oxides are wide bandgap conductors that have found a range of applications in optoelectronic devices. In this study, Hosono and colleagues fabricate the first transparent conducting oxide based on germanium.

    • Hiroshi Mizoguchi
    • , Toshio Kamiya
    •  & Hideo Hosono
  • Article |

    Property coupling by heteroepitaxy is severely limited in material combinations with highly dissimilar bonding. This report presents a chemical boundary condition methodology to actively engineer two-dimensional film growth in such systems that otherwise collapse into island formation and rough morphologies.

    • Elizabeth A. Paisley
    • , Mark. D. Losego
    •  & Jon-Paul Maria
  • Article |

    Multiple scattering complicates femtosecond optics such that phase conjugation allows spatial focusing and imaging through a multiple scattering medium, but temporal control is problematic. McCabeet al. report the full spatio-temporal characterization and recompression of a femtosecond speckle field.

    • David J. McCabe
    • , Ayhan Tajalli
    •  & Béatrice Chatel
  • Article
    | Open Access

    At extreme temperature and pressure, materials can form new dense phases with unusual physical properties. Here, laser-induced microexplosions are used to produce a superdense, stable, body-centred-cubic form of aluminium, which was previously predicted to exist at pressures above 380GPa.

    • Arturas Vailionis
    • , Eugene G. Gamaly
    •  & Saulius Juodkazis
  • Article
    | Open Access

    Being able to determine the wetting properties of individual nanoparticles would aid the preparation of particles with controlled surface properties. Isaet al. develop an in situ freeze-fracture shadow-casting method and use this to determine structural and thermodynamic properties of various 10 nm particles at fluid interfaces.

    • Lucio Isa
    • , Falk Lucas
    •  & Erik Reimhult
  • Article
    | Open Access

    Magnesium is an ideal rechargeable battery anode material, but coupling it with a low-cost sulphur cathode, requires a non-nucleophilic electrolyte. Kimet al. prepare a non-nucleophilic electrolyte from hexamethyldisilazide magnesium chloride and aluminium trichloride, and show its compatibility with a sulphur cathode.

    • Hee Soo Kim
    • , Timothy S. Arthur
    •  & John Muldoon
  • Article |

    Single-molecule magnets could be useful for the development of spintronic devices. Here single-molecule magnets are encapsulated in carbon nanotubes without affecting the properties of the guest molecules, which may be useful in the development of spintronic or high-density magnetic storage devices.

    • Maria del Carmen Giménez-López
    • , Fabrizio Moro
    •  & Andrei N. Khlobystov
  • Article |

    Covalent reactions on carbon nanotube surfaces typically occur at random positions on the hexagonal lattice. Denget al. show that Billups–Birch reductive alkylation takes place at, and propagates from, sp3defect sites, leading to confinement of the reaction fronts in the tubular direction.

    • Shunliu Deng
    • , Yin Zhang
    •  & YuHuang Wang
  • Article |

    Single nanoparticles are known to emit light intermittently, or 'blink', but the mechanisms describing this phenomenon are not fully understood. This study demonstrates that, for small clusters of blinking nanoparticles, the number of particles within a cluster dramatically influences blinking time.

    • Siying Wang
    • , Claudia Querner
    •  & Marija Drndic
  • Article
    | Open Access

    Negative thermal expansion—contraction upon heating—is an unusual process that may be exploited to produce materials with zero or other controlled thermal expansion values. Azumaet al. observe negative thermal expansion in BiNiO3which is a result of Bi/Ni charge-transfer transitions.

    • Masaki Azuma
    • , Wei-tin Chen
    •  & J. Paul Attfield
  • Article
    | Open Access

    The conductance of single-molecule junctions is affected by the structure of the molecule and how it is bound to the electrodes, which may be examined using Raman spectroscopy. Liuet al. have developed 'fishing-mode' tip-enhanced Raman spectroscopy, which allows the simultaneous determination of conductance and Raman spectra.

    • Zheng Liu
    • , Song-Yuan Ding
    •  & Zhong-Qun Tian
  • Article |

    Little is known about the effects of molecular crowding and confinement on biomolecule function. Castronovoet al. investigate the reactions of restriction enzymes with DNA confined in bushy matrices and find that the enzymes enter at the side of the matrix before diffusing two-dimensionally.

    • Matteo Castronovo
    • , Agnese Lucesoli
    •  & Giacinto Scoles
  • Article
    | Open Access

    Temperature-controlled regulation of thermal conductivity is difficult to achieve because thermal properties do not change significantly through solid-state phase transitions. Here temperature control of thermal conductivities is demonstrated using liquid–solid phase transitions in a nanoparticle suspension.

    • Ruiting Zheng
    • , Jinwei Gao
    •  & Gang Chen
  • Article |

    Melting-related phenomena are of fundamental and applied interest, but the melting theory is poorly understood. Levitas and Samani develop an advanced phase-field theory of melting coupled to mechanics that resolves existing contradictions and reveals the features of melting phenomena.

    • Valery I Levitas
    •  & Kamran Samani
  • Article
    | Open Access

    In the pseudogap state of cuprates, although diamagnetic signals have been detected, a Meissner effect has never been observed. Morenzoni and colleagues probe the local diamagnetic response in the normal state of an underdoped layer showing that a 'barrier' layer exhibits a Meissner effect.

    • Elvezio Morenzoni
    • , Bastian M. Wojek
    •  & Ivan Božović
  • Article
    | Open Access

    Observing superposition states of mesoscopic quantum systems is an ongoing challenge. Gerlichet al. report quantum interference of large tailor-made organic compounds, demonstrating delocalization and the quantum wave nature of entire molecules composed of up to 430 atoms.

    • Stefan Gerlich
    • , Sandra Eibenberger
    •  & Markus Arndt
  • Article |

    Monitoring the impact of annealing on nanometre-thick polymer layers provides new insight into the changes in the performance of macromolecular materials. Here, the authors present results showing a correlation between the deviations from bulk behaviour and the growth of an irreversibly adsorbed layer.

    • Simone Napolitano
    •  & Michael Wübbenhorst
  • Article |

    The formation of hydrophilic protein–protein interactions cannot be explained by charge–charge interactions. Here, molecular simulations reveal that water forms an adhesive hydrogen-bonded network between proteins, stabilizing intermediate states before the bound complex forms.

    • Mazen Ahmad
    • , Wei Gu
    •  & Volkhard Helms
  • Article |

    Defining the structure of amorphous solids is a challenge because of their lack of structural order. In this study, the authors combine experiment and theory to analyse the surface of amorphous selenium, and show that the differences between surface and bulk are attributable to a particular type of coordination defect.

    • T. Scopigno
    • , W. Steurer
    •  & T. Wagner
  • Article
    | Open Access

    Distinguishing closely related molecules using chemosensor materials is a continuing challenge. Here, an entangled porous coordination polymer is developed, which confines volatile organic compounds, and allows photoluminescence-based distinction of structurally similar aromatic molecules.

    • Yohei Takashima
    • , Virginia Martínez Martínez
    •  & Susumu Kitagawa
  • Article
    | Open Access

    Molecular fluctuations are a source of noise that can impede single-molecule identification. Here, quantum-fluctuation-induced inelastic noise is observed as current fluctuations in individual molecules, suggesting that inelastic noise could be used as a molecular signature.

    • Makusu Tsutsui
    • , Masateru Taniguchi
    •  & Tomoji Kawai
  • Article |

    The spatial scale over which metal–insulator transitions happen is not known, despite the importance of this phenomenon in basic and applied research. The authors show that in chromium-doped V2O3, with decreasing temperature, microscopic metallic domains coexist with an insulating background.

    • S. Lupi
    • , L. Baldassarre
    •  & M. Marsi
  • Article
    | Open Access

    Understanding the thermal transitions of confined polymers is important for the design of molecular scale devices. In this study, unusual thermal transitions are observed in polyethylene glycol chains incorporated in nanochannels of porous coordination polymers.

    • Takashi Uemura
    • , Nobuhiro Yanai
    •  & Susumu Kitagawa
  • Article |

    One challenge in the development of proton exchange fuel cells is the requirement for durable, high-conductivity electrolytes. The authors show that incorporating ionic liquids into synthetic block co-polymer electrolytes results in nanostructured membranes with much higher conductivities than currently available.

    • Sung Yeon Kim
    • , Suhan Kim
    •  & Moon Jeong Park
  • Article |

    The spontaneous ordering of molecules into two-dimensional arrays is usually a result of directional intermolecular interactions. Here, it is shown that electrospray-deposited Mn12(acetate)16forms filamentary aggregates driven by anisotropic interactions, which are a consequence of the complex shape of the molecule.

    • Alex Saywell
    • , Graziano Magnano
    •  & Peter H. Beton
  • Article
    | Open Access

    Chemical systems with switchable molecular spins could allow the development of materials with controllable spintronic properties. Here, the authors show that nitric oxide coordination to cobalt(II)tetraphenylporphyrin on a nickel surface, followed by thermal dissociation, leads to off-on spin switching.

    • Christian Wäckerlin
    • , Dorota Chylarecka
    •  & Nirmalya Ballav