The nature of coinage-metal bonds between AuX (X = F, Cl, Br, CN, NO2, CH3) and aromatic moieties with different electronic properties (benzene, 1,3,5-trifluorobenzene and hexafluorobenzene) has been characterized within...

We presented a theoretical study on the detailed reaction mechanism and kinetics of the CN radical with the HNCS molecule. The barrierless minimum energy path and the most favorable entrance channel have been determined by constructing a two-dimensional potential energy surface of the C atom of CN attacking the HNCS molecule. The reaction of the C atom attacking the S atom was finally identified as the dominant entrance channel based on the rate constants' results calculated with the canonical variational transition state theory. The master equation method was employed to calculate the products' branching ratios, the overall rate constant, and the pressure dependence of the title reaction. The B3LYP∕6-311+G(2d,p) method was employed for all the geometrical optimizations and a multi-level extrapolation method based on the CCSD(T) and MP2(FC) energies was employed for further energy refinements.

The parallel-shaped complexes OCS … hydrocarbon, CO 2 … hydrocarbon, and N 2 O … hydrocarbon (hydrocarbon ＝ ethylene, acetylene, dimethylacetylene) were investigated at the MP2/aug-cc-pVDZ level. The interaction energies are along the sequence of B…C 2 H 4 ＜B…C 2 H 2 ＜B… C 4 H 6 (B＝OCS, CO 2 , N 2 O), and the interaction distances are in sequence of B…C 2 H 4 ＞B…C 2 H 2 ＞B… C 4 H 6 (B＝OCS, CO 2 , N 2 O). The π…π interactions were investigated by using the topological analysis of electron density. The nature of interactions of the parallel-shaped complexes belongs to weak electrostatic interactions. The bond paths in the molecular graphs of π electron density and total electron density show the same orientation, indicating that the π…π interactions play an important role in these intermolecular interactions. NBO analyses showed that charge transfers were observed from C 2 H 4 , C 2 H 2 , C 4 H 6 to OCS, CO 2 , N 2 O, and the amount of charge transfer are in sequence of B…C 2 H 4 ＜B…C 2 H 2 ＜B…C 4 H 6 (B＝OCS, CO 2 , N 2 O), which exactly match the order of the interaction energies. Keywords intermolecular interaction; the parallel-shaped geometry; topological analysis of electron density; π…π interaction; natural bond orbital (NBO)