A very generous donor : The electrochemiluminescence (ECL) efficiency and radical stability of pyrene, a poor ECL luminophore, are markedly improved as the number of peripheral multidonor units increased in a series of compounds (see picture). Photophysical and electrochemical studies and theoretical calculations have contributed to the understanding of the ECL enhancement, which is a step forward in the development of new light‐emitting materials.
Codeposition of NO and O 2 diluted in Ne at 6 K yield a ON???OO complex that exhibit strong UV absorption. This complex is converted into NO3 radicals by UV irradiation, and is regenerated by radiation of visible light (see spectra).
Highly active, selective, and stable : Highly ordered mesoporous carbon without deposition of metal particles catalyzes the oxidative dehydrogenation of ethyl benzene to styrene. A high activity and selectivity as well as long catalytic stability when compared with activated carbon, is observed from this catalyst.
New pH‐sensitive probe design : A peek into the structure of fluorescent proteins led to the synthesis of fluorescent imidazoles. The prepared compounds demonstrated an array of remarkable pH‐dependent optical properties including at least two types of excited‐state charge transfers (see picture).
Particle vs tube : The present paper systematically investigates a range of fundamental geometrical and structural features of TiO2 nanotube layers and their effect on the dye‐sensitized solar cell conversion efficiency, to deduce the most promising strategies for improvement. It is found that the performance of the cells strongly depends on the morphology and crystalline structure of the nanotubes.
Structural colors: Poly(N‐isopropyl acrylamide) based microgel photonic crystals are fabricated by using a new method called “high‐temperature‐induced hydrophobic assembly”. The assembling conditions affect the water content of the crystals, thus determining their structural color (see image). The obtained photonic crystals are sensitive to solvents, and the reversible changes in their color can be observed with the naked eye.
Weak and robust ? Tetraalkylammonium salts of weakly coordinating fluorinated alkoxyaluminates are easily accessible, chemically robust materials that show interesting physico‐chemical properties like low melting points, high electrochemical stability and electric conductivity in weakly polar solvents such as CH2Cl2, Ph‐F and toluene.
Fluoro power : In agreement with theoretical studies on α‐fluorocarbanions an X‐ray crystal structure shows the α‐fluorobis(phenylsulfonyl)methide anion adopts a pyramidal configuration (see picture). High‐level calculations and NMR spectroscopy studies demonstrate that electron‐withdrawing substituents play a crucial role in modulating the properties of bis(phenylsulfonyl)methide anions.
Work‐alcoholic! The elusive enantioselective catalytic α‐alkylation of aldehydes, a widely sought transformation, was brought to execution by the use of alcohols capable of forming stabilized carbocations (see scheme, TFA=trifluoroacetic acid).
Radically different : Contrary to previous proposals, the main reaction of the HO. radical with guanosine or 2′‐deoxyguanosine is the hydrogen abstraction from the NH2 moiety to give a guanyl radical. This radical, characterized by a broad band in the visible region (around 610 nm), undergoes tautomerization to the most stable isomer.
Modeling magnetism: The antiferromagnetic ground state of the C60/Si(001)‐c(4×4) surface is predicted by means of density functional theory calculations. Two adjacent dangling bonds (DBs) generated by the adsorption of C60 are antiferromagnetically coupled with each other. This study demonstrates that magnetic Si surfaces can be prepared by engineering single Si DBs with unpaired electrons.
Guest Effect : The differences of nitrogen atom positions and the bridge bonds linked to two pyridine rings of some bipyridine guests can significantly affect the binding abilities and inclusion geometries of β‐cyclodextrin with the guests in both the solution and solid states.
