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Seven-dimensional time-dependent wave packet calculations were carried out to study the title reaction on the potential energy surface constructed recently by the group [Y. Zhou, B. Fu, C. Wang, M. A. Collins, and D. H. Zhang, J. Chem. Phys. 134, 064323 (2011)]. Total reaction probabilities and integral cross sections were calculated for a number of initial vibration states. It is found that the fundamental C-H stretching excitation can promote the reaction dramatically. At E = 1.53 eV, it enhances the integral cross section by a factor of 13.2, which is in good agreement with the quasiclassical trajectory result on the ZBB1 potential energy surface, but larger than that on the the EG-2002 potential energy surface. The thermal rate constants were obtained for the title reaction by taking into account the contributions from all relevant initial vibration states. It is found that the ground initial state has a dominant contribution to the thermal rate constant at low temperature region. As the temperature increases, the relative contribution to the thermal rate constant from the ground initial state decreases quickly, and those from the stretching and bending excited states increases substantially. It is estimated that the C-H stretching mode contributes about 40% of the thermal rate constant at T = 1000 K despite the fact that the overall population for stretching excited states is tiny. [ABSTRACT FROM AUTHOR]

A new full-dimensional potential energy surface for the title reaction has been constructed using the modified Shepard interpolation scheme. Energies and derivatives were calculated using the UCCSD(T) method with aug-cc-pVTZ and 6-311++G(3df,2pd) basis sets, respectively. A total number of 30 000 data points were selected from a huge number of molecular configurations sampled by trajectory method. Quantum dynamical calculations showed that the potential energy surface is well converged for the number of data points for collision energy up to 2.5 eV. Total reaction probabilities and integral cross sections were calculated on the present surface, as well as on the ZBB3 and EG-2008 surfaces for the title reaction. Satisfactory agreements were achieved between the present and the ZBB3 potential energy surfaces, indicating we are approaching the final stage to obtain a global potential energy surface of quantitative accuracy for this benchmark polyatomic system. Our calculations also showed that the EG-2008 surface is less accurate than the present and ZBB3 surfaces, particularly in high energy region. [ABSTRACT FROM AUTHOR]

Abstract: A six-dimensional state-to-state quantum dynamics study is carried out for the prototypical complex-formation OH+CO→H+CO2 reaction from the ground and two vibrationally excited initial states on the Lakin–Troya–Schatz–Harding potential energy surface for the total angular momentum J =0, using the multiple-step reactant–product decoupling method. With three heavy atoms and deep wells on the reaction path, the reaction represents a huge challenge for accurate quantum dynamics study. The effects of reagent vibrational excitation on product CO2 vibrational state distributions and product energy partition were investigated for reagents in the ground rotational state. It is found that the initial CO vibrational excitation essentially has the same effect on the product energy partition as the reagent translational excitation, while the initial OH excitation leads to slightly more internal energy in CO2. [Copyright &y& Elsevier]

CaS and SrS nanocrystallites have been successfully synthesized via a solvothermal route by the reaction between XCl2 (X=Ca, Sr) and sulfur at relatively lower temperature for the first time. XS (X=Ca, Sr) nanocrystallites are efficient emission luminescence in comparison with that of bulk materials at room temperature. The emitted light of CaS and SrS nanocrystallites is yellow–green and blue, respectively. [Copyright &y& Elsevier]