Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
The following papers are very important in the opinion of two referees.
Luminescence Properties of Ca2Ga2SiO7:RE Phosphors for UV White-Light-Emitting Diodes
Dr. Mengmeng Jiao, Wenzhen Lv, Wei Lü, Qi Zhao, Baiqi Shao and Prof. Hongpeng You
Lighting up: Eu2+-, Ce3+-, and Tb3+-doped novel Ca2Ga2SiO7 phosphors are presented with detailed structure and luminescence properties. The Ca2Ga2SiO7:Eu2+ and Ca2Ga2SiO7:Ce3+ phosphors might have potential value in serving as UV excited green and blue phosphors for white-light-emitting diodes.
Single-Molecule Methods to Study Membrane Receptor Oligomerization
Franziska Fricke, Marina S. Dietz and Prof. Dr. Mike Heilemann
Singles′ party: Single-molecule techniques suitable for studying the oligomerization of membrane receptors are reviewed: photobleaching, Förster resonance energy transfer, localization microscopy and co-tracking. Experimental requirements, benefits and difficulties are discussed and biological applications are highlighted.
High Accuracy of Karplus Equations for Relating Three-Bond J Couplings to Protein Backbone Torsion Angles
Dr. Fang Li, Dr. Jung Ho Lee, Dr. Alexander Grishaev, Dr. Jinfa Ying and Dr. Ad Bax
The right match: 3JHNHα and 3JC′C’ couplings both are related to protein backbone dihedral angles through Karplus equations. However, the relation between 3JHNHα and is indirect as it relies on the unknown exact position of backbone hydrogens, making 3JC′C′ the better reporter for .
Photoelectron Circular Dichroism of Bicyclic Ketones from Multiphoton Ionization with Femtosecond Laser Pulses
Christian Lux, Prof. Dr. Matthias Wollenhaupt, Cristian Sarpe and Prof. Dr. Thomas Baumert
Nodes in circular dichroism resolved: Chiral recognition in the gas phase on randomly oriented chiral molecules using femtosecond laser pulses is reported. The picture shows circular dichroism from (S)-(−)-camphor observed on the 3D momentum distribution of ejected photoelectrons after three-photon ionization. The pink areas represent positive and the turquoise areas represent negative signals. Note the antisymmetry with respect to the laser propagation.
Exploring the Free Energy and Conformational Landscape of tRNA at High Temperature and Pressure
Caroline Schuabb, Melanie Berghaus, Christopher Rosin and Prof. Dr. Roland Winter
RNA under pressure! Exploration of the conformational and free-energy landscape of the 76-residue yeast phenylalanine transfer RNA (tRNAPhe; see figure) reveals that RNA unfolding differs not only from protein unfolding but also from DNA melting. Compared with the pronounced temperature effect, pressure-dependent changes in the secondary structure of tRNAPhe are small, however, even up to the 1000 MPa range.
Electrocatalytic Oxidation and Adsorption Rate of Methanol at Pt Stepped Single-Crystal Electrodes and Effect of Ru Step Decoration: A DEMS Study
Dr. Ehab Mostafa, Dr. Abd-El-Aziz A. Abd-El-Latif and Prof. Dr. Helmut Baltruschat
Methanol adsorption rate: At Pt electrodes, methanol is oxidized either to dissolved intermediates or—in parallel—to CO2 via adsorbed CO. The adsorption rate of methanol is dependent on the surface structure and increases with the step density. A further increase is observed upon step decoration by Ru.
Interphase Evolution at Two Promising Electrode Materials for Li-Ion Batteries: LiFePO4 and LiNi1/2Mn1/2O2
Dr. Nicolas Dupré, Dr. Marine Cuisinier, Dr. Jean-Frederic Martin and Dr. Dominique Guyomard
The importance of the chemical history of the electrode surface before electrochemical cycling as well as the correlation between interface phenomena, the formation/evolution of an interphase, and the electrochemical behavior of LiFePO4 and LiNi1/2Mn1/2O2 electrodes are investigated by magic-angle-spinning nuclear magnetic resonance, electron energy loss spectroscopy, and X-ray photoelectron spectroscopy. These techniques allow the study of interface aging and failure mechanisms.
Ethanol Oxidation on Pt Single-Crystal Electrodes: Surface-Structure Effects in Alkaline Medium
Carlos Busó-Rogero, Prof. Enrique Herrero and Prof. Juan M. Feliu
Inverted reactivity order: Ethanol oxidation on platinum single-crystal electrodes in alkaline solutions produces mainly acetate and the activity order is the opposite of that found in acid solutions. The formation of acetaldehyde deactivates the surface (see picture).
Electrocatalytic Oxygen Reduction Reaction on Perovskite Oxides: Series versus Direct Pathway
T. Poux, A. Bonnefont, G. Kéranguéven, G. A. Tsirlina, E. R. Savinova*
Are oxides of the perovskite family, which have recently attracted much interest, promising materials for cathodes of solid and liquid alkaline fuel cells? How does their electrocatalytic activity and selectivity depend on the nature of the oxide, its loading, and the carbon addition? Does the oxygen reduction on perovskite oxides follow a “direct” 4 e- path, or is the O2 molecule first reduced to hydrogen peroxide and only then to water? These and other questions are addressed in the article by combining a rotating-ring-disc study with kinetic modeling.
Received February 09, 2014, published online May 14, 2014, DOI: 10.1002/cphc.201402022 – read now.
Two-Color RESOLFT Nanoscopy with Green and Red Fluorescent Photochromic Proteins
Flavie Lavoie-Cardinal, Nickels A. Jensen, Volker Westphal, Andre C. Stiel, Andriy Chmyrov, Jakob Bierwagen, Ilaria Testa, Stefan Jakobs,* Stefan W. Hell*
Dual-color live-cell RESOLFT superresolution microscopy is demonstrated with green- and red-emitting switchable fluorescent protein tags. The red-emitting tag is a novel reversibly switchable protein, rsCherryRev1.4, enabling a resolution up to four times over the diffraction barrier. Dual-color RESOLFT works with both single and multiple ‘donuts’ using more than 23000 ‘donuts’ in parallel.
Received November 04, 2013, published online January 21, 2014, DOI: 10.1002/cphc.201301016 – read now.
On the Electrochemical Deposition and Dissolution of Divalent Metal Ions
Wolfgang Schmickler,* Leandro M. C. Pinto, Paola Quaino, Elizabeth Santos
Divalent metal ions like Cu++ and Zn++ have strong solvation shells and cannot be deposited directly. They first undergo an outer-sphere electron transfer to the monovalent ions, which fit well into the water structure and can be deposited. In the case of copper, the energy of Cu+ is only a little higher than that of Cu++, and this path is favorable. In contrast, the energy of Zn+ is too high to be a favorable intermediate. In accord with experimental data, the authors suggest that zinc deposition is catalyzed by anions.
Received September 15, 2013, published online December 02, 2013, DOI: 10.1002/cphc.201300856 – read now.
O-H···N and C-H···O Hydrogen Bonds Control Hydration of Pivotal Tropane alkaloids: Tropinone···H2O Complex
Patricia Écija, Montserrat Vallejo-López, Luca Evangelisti, José A. Fernández, Alberto Lesarri, Walther Caminati, Emilio J. Cocinero*
The effect of monohydration in the equatorial/axial isomerism of the common motif of tropane alkaloids has been investigated in a supersonic expansion by using Fourier-transform microwave spectroscopy. The rotational spectrum reveals that the equatorial isomer is the dominant species in tropinone···H2O. We show how water interacts with tropinone, forming a hydrogen bond with the amino group rather than with the carboxylic group.
Received December 22, 2013, published online February 24, 2014, DOI: 10.1002/cphc.201301213 – read now.
From Molecular Structure to Spectroscopic and Material Properties: Computational Investigation of a Bent-Core Nematic Liquid Crystal
Alberta Ferrarini, Cristina Greco, Elisa Frezza, Alberto Marini
Bent-core liquid crystals have a number of unconventional properties that remain the object of debate. By means of an integrated theoretical and computational methodology, Ferrarini and colleagues are able to bridge the molecular structure to the materials' properties. The authors simultaneously predict 13C-NMR chemical shifts, which are defined with atomistic resolution, and elastic constants that control deformations on the macroscopic scale. By a proper account of the molecular geometry, the researchers show that the unusual bend elasticity of these systems subtly depends on their bent shape.
Received November 06, 2013, published online January 27, 2014, DOI: 10.1002/cphc.201301030 – read now.
Non-Uniform Helix Unwinding of Cholesteric Liquid Crystals in Cells with Interdigitated Electrodes
Mariacristina Rumi, Vincent P. Tondiglia, Lalgudi V. Natarajan, Timothy J. White, Timothy J. Bunning
In liquid crystal cells with interdigitated electrodes, the electro-optic response of cholesteric materials to an electric field applied perpendicular to the helical axis is found to depend on the geometrical parameters of the cells. In particular, in cells with narrow gaps between electrodes, the unwinding of the cholesteric helix in response to an electric field occurs in a non-uniform manner through the thickness of the cell, due to a large field gradient. This heterogeneity leads to different pitches and selective Bragg reflection wavelengths on the cell side with the patterned electrodes compared to the opposite cell side.
Received October 28, 2013, published online January 02, 2014, DOI: 10.1002/cphc.201300995 – read now.
Reorientational Dynamics of Water Confined in Zeolites
Damien Laage, Aoife C. Fogarty, François-Xavier Coudert, Anne Boutin
Situations in which water is strongly confined are of great importance in many contexts, ranging from biochemistry to chemical engineering, and such a confinement is known to affect the properties of water. The authors combine numerical simulations and analytic modeling to analyze the impact of an extreme hydrophobic confinement, such as that found in some zeolites, on water dynamics. Their results suggest that the main perturbation is due to the presence of the interface –and to its chemical nature– and to a lesser extent to confinement.
Received October 09, 2013, published online January 21, 2014, DOI: 10.1002/cphc.201300928 – read now.