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A recent experiment on the 267 nm photolysis of gaseous acetaldehyde reveals that the molecular products (CO + CH4) present product state distributions with computation –experiment discrepancy. This work aims to provide solution to such issue. The direct dynamics simulation of classical trajectories and the generalized multi‐center impulsive model (GMCIM) are both utilized to predict the product state distributions of CO and CH4 from 267 nm photolysis of acetaldehyde. Comparison with the experimental observation provides an assessment of the conventional approach of minimum energy path within the framework of three‐center transition state (TS) and CH3‐roaming pathways. The result shows that the high‐speed products observed in experiment are likely formed via the three‐center TS pathway. The reasons that lead to the discrepancy between computation and experiments in previous studies are also investigated. A better agreement between computational and state‐resolved experimental results can be achieved by selecting specific internal states of CO product from the computational data. [ABSTRACT FROM AUTHOR]

We utilize single molecule spectroscopy combined with time-correlated single-photon counting to probe electron transfer (ET) kinetics from CdSe/ZnS (core/shell) quantum dots (QDs) to TiO2 through various lengths of linker molecules. The QD-linker-TiO2 complexes with varied linker length, linker structure, and QD size are fabricated by a surface-based stepwise method to show control of the rate and of the magnitude of fluctuations of photo-induced ET at the single molecule level. The ET rate constants are determined to be 2.8×107, 1.9×107, and 3.5×106 s−1 for the chain length of 1.5, 6.2 and 13.8 Å, respectively. The electronic coupling strengths between QDs and TiO2 are further calculated to be 3.68, 3.60, and 1.59 cm−1 for the three different chain lengths by using the Marcus ET model. [ABSTRACT FROM AUTHOR]

Experimental studies on reaction dynamics by use of molecular beams and oriented molecular beams are reviewed in order for looking closer to chemical reactions as well as photodissociations at the molecular level. We discuss about versatility and usefulness of the electrostatic hexapole sate-selector as a non-destructive selector for molecular structure analysis. Some experimental evidences on novel reaction dynamics in photodissociation and stereodynamics are presented followed by concluding remarks and future perspectives for controlling chemical reactions from the point of view of green chemistry, by manipulating molecular orientation without any catalyst nor by applying any external forces like intense electromagnetic field. [ABSTRACT FROM AUTHOR]