With an increase in temperature, an unprecedented restoration of symmetry in the symmetry breaking excited state charge transfer is observed in a geminal pair of near-orthogonally connected perylenimide dimers. Such restoration of symmetry could be attributed to the interchromophoric planarization and/or loss of solvation asymmetry at elevated temperature resulting in enhanced fluorescence quan...

Ultracold collisions between Cs atoms and Cs2 dimers in the electronic ground state are observed in an optically trapped gas of atoms and molecules. The Cs2 molecules are formed in the triplet ground state by cw photoassociation through the outer well of the 0-(g) (P3/2) excited electronic state. Inelastic atom-molecule collisions converting internal excitation into kinetic energy lead to a los...

The regio- and diastereoselective zirconocene-catalyzed carbomagnesiation of cyclobutenes is herein reported to afford configurationally stable cyclobutylmagnesium species that could subsequently react with a large variety of electrophiles to give polysubstituted cyclobutane species as a single diastereoisomer.

The asymmetric unit of the title compound, C(17)H(12)O, contains two molecules, in which the fused aromatic ring systems are almost planar [maximum deviations = 0.0529 (9) and 0.0256 (9) Å]. In the crystal, aromatic π-π stacking inter-actions (perpendicular distance of centroids of about 3.4 Å) and strong O-H⋯O hydrogen bonds result in a helical arrangement of pyrenyl dimers.

A conformational analysis has been carried out for monoprotonated, unprotonated and deprotonated glycine dimers in the gas phase an aqueous solution. MP2/6-311++(d,p), B3LYP/6-311++(d,p) M06/6-311++(d,p) optimizations were performed more than 200 initial conformations comprising nonionic (COOH–CH2–NH2) (N) zwitterionic (COO−–CH2–NH3+) (Z) structures neutral monomers. All methods indicate that Z...

Placing a fluid mixture in temperature gradient can cause concentration gradients to build up, phenomenon called the Soret effect. The authors simulate this effect for of monomers and dimers, find contribution from internal degrees freedom dimers. Under some conditions sign is reversed.

4,6-Dichloro-2-(methylthio)pyrimidine (3) reacts with EtONa in EtOH, at ca. 20 ◦C, for 2 h, to give exclusively 4-chloro-6-ethoxy-2-(methylthio)pyrimidine (5) in 89% yield. The latter is presented as a useful multifunctionalised pyrimidine scaffold.

We study perfect matchings, or close-packed dimer coverings, of finite sections the eleven Archimedean lattices and give a constructive proof showing that any two matchings can be transformed into each other using small sets local ring-exchange moves. This result has direct consequences for formulating quantum models with resonating valence bond ground state, i.e., superposition all coverings c...