Quantum mechanical study of the F + D2 → DF + D reaction

INVESTIGATION OF THE CONTRIBUTION FOR THE NONCOLLINEAR CHANNEL OF THE F(2P3/2,2P1/2) + H2/D2 REACTIONS ON FOUR DIABATIC POTENTIAL ENERGY SURFACES

We performed the nonadiabatic time-dependent wave packet calculation on the four diabatic potential energy surfaces, which have the different barrier height, to investigate the contribution of the noncollinear channel for the F (2P) + H2/D2 (v = j = 0) reactions. The reaction probabilities, integral cross-sections, and rate constants are presented. The results indicate that the probabilities as the function of the collision energy have an obvious translation. The reactive activity of the reactions comes from the noncollinear reactive channel. The bent barrier height would decrease the reactive activity. The integral cross-sections are in the order of AWS < LWA-5 < LWA-78 ≈ MASW, which is opposite to that of the bent barrier height. At the lower temperature, the difference of the rate constants is unambiguous. As the temperature increases, the difference reduces. At the higher temperature, the rate constants computed on the four potential energy surfaces are close.

The investigation of spin–orbit effect for the F(2P)+HD reaction

In this paper, we employ the time-dependent quantum wave packet method to study the reaction of F((2)P(3/2), (2)P(1/2)) with HD on the Alexander-Stark-Werner potential energy surface. The reaction probabilities and total integral cross sections of the spin-orbit ground and excited states for the two possible products of the system are calculated. Because the reaction channel of the excited spin-orbit state is closed at the resonance energy, the resonance feature does not appear in the reaction probabilities and cross section for the F((2)P(1/2))+HD(v=j=0)-->HF+D reaction, in contrast with that found for the ground spin--orbit state. We also compare the average cross sections of the two possible products with the experimental measurement. The resonance peak in the present average cross section for the HF+D product is slightly larger than the experimental result, but much smaller than that of the single-state calculations on the potential energy surface of Stark and Werner. It seems that the spin--orbit coupling would play a relatively important role in this reaction. Moreover, the isotope effects of the ground and excited spin--orbit states and the reactivity of the two product channels from the excited spin--orbit state are presented.

Quantum scattering calculations on chemical reactions

This review discusses recent quantum scattering calculations on bimolecular chemical reactions in the gas phase. This theory provides detailed and accurate predictions on the dynamics and kinetics of reactions containing three atoms. In addition, the method can now be applied to reactions involving polyatomic molecules. Results obtained with both time-independent and time-dependent quantum dynamical methods are described. The review emphasises the recent development in time-dependent wave packet theories and the applications of reduced dimensionality approaches for treating polyatomic reactions. Calculations on over 40 different reactions are described.

Insertion and abstraction pathways in the reaction O(1D2) + H2-->OH+H

Rigorous quantum dynamical calculations have been performed on the ground 1 1A' and first excited 1 1A" electronic states of the title reaction, employing the most accurate potential energy surfaces available. Product rovibrational quantum state populations and rotational angular momentum alignment parameters are reported, and are compared with new experimental, and quasiclassical trajectory calculated results. The quantum calculations agree quantitatively with experiment, and reveal unequivocally that the 1 1A" excited state participates in the reaction.

CROSSED-BEAM STUDIES OF REACTION DYNAMICS

▪ Abstract  This article reviews recent progress in our understanding of gas-phase neutral reaction dynamics as made possible by improvements in the crossed molecular beam scattering technique for measuring reactive differential cross sections. A selection of crossed-beam studies on systems that play a fundamental role in our basic understanding of reaction phenomena are discussed to illustrate the capabilities of the experimental method. The examples include benchmark atom-diatom abstraction and insertion reactions, and four-atom radical reactions for which state-to-state, state-resolved, or state-averaged differential cross sections have recently been measured. The results are discussed in the light of the latest related theoretical developments regarding the treatment of potential energy surfaces and the dynamics of the systems. Recent results on crossed-beam studies of chemically relevant reactions of carbon, nitrogen, and oxygen atoms are also reviewed, and the latest developments in the technique are noted.