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Recently reported highly fluorescent 2-phenylbenzo[b]phospholium salt shows an interesting photochemical property. While the counter anion and solvent dependency indicate that the salt is mainly responsible for the absorption and fluorescence spectra, the fluorescence decay clearly depends on the counter anion. In the present study, the detailed mechanism is elucidated using quantum chemical computation and its hybrid with statistical mechanics called 3D-RISM-SCF. Based on the careful exploration of plausible structures of the ion pairs in the methanol and dichloromethane solution, we identify the structure of the charge transfer state, the key on the photoprocess.

A ground-breaking empirical valence bond study for a soluble transition-metal complex is presented. The full reaction of catalyst monomers approaching and reacting in the Ru-V oxidation state were studied. Analysis of the solvation shell in the reactant and along the reaction coordinate revealed that the oxo itself is hydrophobic, which adds a significant driving force to form the dimer. The effect of the solvent on the reaction between the prereactive dimer and the product was small. The solvent seems to lower the barrier for the isoquinoline (isoq) complex while it is increased for pyridines. By comparing the reaction in the gas phase and solution, the proposed p-stacking interaction of the isoq ligands is found to be entirely driven by the water medium.

A ground-breaking empirical valence bond study for a soluble transition-metal complex is presented. The full reaction of catalyst monomers approaching and reacting in the Ru-V oxidation state were studied. Analysis of the solvation shell in the reactant and along the reaction coordinate revealed that the oxo itself is hydrophobic, which adds a significant driving force to form the dimer. The effect of the solvent on the reaction between the prereactive dimer and the product was small. The solvent seems to lower the barrier for the isoquinoline (isoq) complex while it is increased for pyridines. By comparing the reaction in the gas phase and solution, the proposed p-stacking interaction of the isoq ligands is found to be entirely driven by the water medium., QC 20170620

A ground-breaking empirical valence bond study for a soluble transition-metal complex is presented. The full reaction of catalyst monomers approaching and reacting in the Ru-V oxidation state were studied. Analysis of the solvation shell in the reactant and along the reaction coordinate revealed that the oxo itself is hydrophobic, which adds a significant driving force to form the dimer. The effect of the solvent on the reaction between the prereactive dimer and the product was small. The solvent seems to lower the barrier for the isoquinoline (isoq) complex while it is increased for pyridines. By comparing the reaction in the gas phase and solution, the proposed p-stacking interaction of the isoq ligands is found to be entirely driven by the water medium.

A ground-breaking empirical valence bond study for a soluble transition-metal complex is presented. The full reaction of catalyst monomers approaching and reacting in the Ru-V oxidation state were studied. Analysis of the solvation shell in the reactant and along the reaction coordinate revealed that the oxo itself is hydrophobic, which adds a significant driving force to form the dimer. The effect of the solvent on the reaction between the prereactive dimer and the product was small. The solvent seems to lower the barrier for the isoquinoline (isoq) complex while it is increased for pyridines. By comparing the reaction in the gas phase and solution, the proposed p-stacking interaction of the isoq ligands is found to be entirely driven by the water medium.

A ground-breaking empirical valence bond study for a soluble transition-metal complex is presented. The full reaction of catalyst monomers approaching and reacting in the Ru-V oxidation state were studied. Analysis of the solvation shell in the reactant and along the reaction coordinate revealed that the oxo itself is hydrophobic, which adds a significant driving force to form the dimer. The effect of the solvent on the reaction between the prereactive dimer and the product was small. The solvent seems to lower the barrier for the isoquinoline (isoq) complex while it is increased for pyridines. By comparing the reaction in the gas phase and solution, the proposed p-stacking interaction of the isoq ligands is found to be entirely driven by the water medium.

A ground-breaking empirical valence bond study for a soluble transition-metal complex is presented. The full reaction of catalyst monomers approaching and reacting in the Ru-V oxidation state were studied. Analysis of the solvation shell in the reactant and along the reaction coordinate revealed that the oxo itself is hydrophobic, which adds a significant driving force to form the dimer. The effect of the solvent on the reaction between the prereactive dimer and the product was small. The solvent seems to lower the barrier for the isoquinoline (isoq) complex while it is increased for pyridines. By comparing the reaction in the gas phase and solution, the proposed p-stacking interaction of the isoq ligands is found to be entirely driven by the water medium.

The monodentate associative chemisorption of molecular oxygen on unclustered graphitic-nitrogen-doped graphene requires two nitrogen dopants per activated molecule. Significant charge transfers from regions corresponding to distant nitrogen-dopants, the presence of a nitrogen-dopant adjacent to the carbon atom acting as an active site, which favours its transition from a sp2 hybridization state to sp3, and the solvation effect turn the investigated mechanism to a favourable process.

The monodentate associative chemisorption of molecular oxygen on unclustered graphitic-nitrogen-doped graphene requires two nitrogen dopants per activated molecule. Significant charge transfers from regions corresponding to distant nitrogen-dopants, the presence of a nitrogen-dopant adjacent to the carbon atom acting as an active site, which favours its transition from a sp2 hybridization state to sp3, and the solvation effect turn the investigated mechanism to a favourable process.

Photolysis of complexes of dimethyl sulfoxide (DMSO) with chlorine atoms results in rapid and permanent photobleaching which may be due to intramolecular hydrogen abstraction. The effects of solvent polarity were examined in a wide variety of DMSO–carbon tetrachloride mixed solvents. The quantum yields of photobleaching decreased from 0.27 to 0.08 as the solvent polarity increased, while significant changes were observed in the low DMSO concentration range (<0.2 mol dm−3). This cannot be accounted for by simple solvent polarity effects. The effects of polar and nonpolar additives were also examined and it is concluded that the specific solvation effect of DMSO was the main cause of the significant change in quantum yields in the low concentration range of DMSO.

Photolysis of complexes of dimethyl sulfoxide (DMSO) with chlorine atoms results in rapid and permanent photobleaching which may be due to intramolecular hydrogen abstraction. The effects of solvent polarity were examined in a wide variety of DMSO–carbon tetrachloride mixed solvents. The quantum yields of photobleaching decreased from 0.27 to 0.08 as the solvent polarity increased, while significant changes were observed in the low DMSO concentration range (<0.2 mol dm−3). This cannot be accounted for by simple solvent polarity effects. The effects of polar and nonpolar additives were also examined and it is concluded that the specific solvation effect of DMSO was the main cause of the significant change in quantum yields in the low concentration range of DMSO.

The simulation of enzymatic reactions, using computer models, is becoming a powerful tool in the most fundamental challenge in biochemistry: to relate the catalytic activity of enzymes to their structure. In the present study, various computed parameters were correlated with the natural logarithm of experimental rate constants for the hydroxylation of various substrate derivatives catalysed by wild-type para-hydroxybenzoate hydroxylase (PHBH) as well as for the hydroxylation of the native substrate (p-hydroxybenzoate) by PHBH reconstituted with a series of 8-substituted flavins. The following relative parameters have been calculated and tested: (a) energy barriers from combined quantum mechanical/molecular mechanical (QM/MM) (AM1/CHARMM) reaction pathway calculations, (b) gas-phase reaction enthalpies (AM1) and (c) differences between the HOMO and LUMO energies of the isolated substrate and cofactor molecules (AM1 and B3LYP/6-31 G(d)). The gas-phase approaches yielded good correlations, as long as similarly charged species are involved. The QM/MM approach resulted in a good correlation, even including differently charged species. This indicates that the QM/MM model accounts quite well for the solvation effects of the active site surroundings, which vary for differently charged species. The correlations obtained demonstrate quantitative structure activity relationships for an enzyme-catalysed reaction including, for the first time, substitutions on both substrate and cofactor.