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The dynamics of C + H2 → H + CH reaction is theoretically studied using the quasiclassical trajectory and quantum mechanical wave packet methods. The analysis of reaction probabilities, integral cross sections, and rate coefficients reveal the essential Coriolis coupling effects in the quantum mechanical wave packet calculations. The calculated polarization-dependent differential cross section, P(θr ) and P(ϕr ) show that the j ′ of product rotational angular momentum is not only aligned along the y axis and the direction of the vector x + z , but also strongly oriented along the positive y axis.

State-to-state time-dependent quantum dynamics calculations have been carried out to study H + DH’ → HH’ + D/HD + H’ reactions on BKMP2 surface. The total integral cross sections of both reactions are in good agreement with earlier theoretical and experimental results, moreover the rotational state-resolved reaction cross sections of H + DH’ → HH’ + D at collision energy E C = 0.5 eV are closer to the experimental values than the ones calculated by Chao et al. [J. Chem. Phys. 117 8341 (2002)], which proves the higher precision of the quantum calculation in this work. In addition, the state-to-state dynamics of H + DH’ → HD’ + H reaction channel have been discussed in detail, and the differences of the micro-mechanism of the two reaction channels have been revealed and analyzed clearly.

We carry out quantum scattering dynamics and quasi-classical trajectory (QCT) calculations for the O + H 2 + reactive collision in the ground (12A″) and first excited (12A′) potential energy surface. We calculate the reaction probabilities of O + H 2 + ( v = 0 , j = 0 ) → OH + + H and O + H 2 + ( v = 0 , j = 0 ) → OH + H + reaction for total angular momentum J = 0. The results calculated by QCT are consistent with those from quantum mechanical wave packet. Using the QCT method, we generate in the center-of-mass frame the product state-resolved integral cross-sections (ICSs); two commonly used generalized polarization-dependent differential cross-sections (PDDCSs), (2π/σ)(dσ 00/dω t), (2π/σ)(dσ 20/dω t); and three angular distributions of the product rotational vectors, P(θ r), P(ϕ r), and P(θ r, ϕ r). We discuss the influence on the scalar and vector properties of the potential energy surface, the collision energy, and the isotope mass. Since there are deep potential wells in these two potential energy surfaces, their kinetic characteristics are similar to each other and the isotopic effect is not obvious. However, the well depths and configurations of the two potential energy surfaces are different, so the effects of isotopic substitution on the integral cross-section and the rotational polarization of product are different.

A globally accurate potential energy surface is reported for the electronic ground-state H2O+. The ab initio energies utilized to map the potential energy surface are calculated at the multireference configuration interaction method employing the aug-cc-pVQZ basis set and the full valence complete active space wave function as reference. In order to improve accuracy of the resulting raw ab initio energies, they are then extrapolated to the complete basis set limit and most importantly to the full configuration-interaction limit by semiempirically correcting the dynamical correlation using the double many-body expansion-scaled external correlation method. The topographical features of the current potential energy surface were examined in detail, which agree nicely with those of other theoretical work.