The Study Of State-to-state Dynamics Of Some A+BC Type Reactions

Molecular reaction dynamics,also called microscopic reaction dynamics,is a discipline to analyze the motion and interaction between molecules based on the microscopic properties of atoms and molecules,so as to deeply understand the nature of chemical reactions and their laws The state-to-state reaction dynamics not only gives us a more intuitive understanding of the internal reaction mechanism of the chemical reaction,but also provides an accurate physical image for the elementary reaction process.In this paper,we performed a quantum state-to-state dynamics calculation of the F+HO reaction,O++H2 reaction,D+ND reaction and S++H2 reaction using the product coordinate based on time-dependent wave packet(TDWP)method developed on GPU,presented the reaction probability,integral cross section(ICS)and differential cross section(DCS),and investigated the reaction mechanism of these reactionsFirstly,we studied the quantum state-to-state dynamics of the F(2P)+HO(2?)?O(3P)+HF(1?+)reaction on the 13A' and 23A" potential energy surfaces(PESs)using the product Jacobi coordinate based TDWP method,with emphasis on the different dynamical behaviors of the reaction on the two excited PESs.It is found that there is obvious vibrational and rotational inversion in the state-resolved ICS on 13A' PES,but the rotational inversion does not appear on 23A" PES.The total and state-resolved DCSs on two PESs exhibit the behavior of sideward and backward scattering,and the sideward scattering is enhanced with the increase of the collision energy.In addition,both the rotational state-resolved ICSs and DCSs show the multi-peak structure,which can be attributed to the quantum interference of the resonance wave functionsBased on the H2O+(X4A")PES constructed by Song et al.,we studied the quantum state-to-state dynamics of the O++H2(v=0,j=0)? OH++H reaction using the TDWP method of the product Jacobi coordinate.By calculation,we obtained the reaction probability,state-resolved ICS and DCS of the reaction.Because of the existence of the potential well in the reaction,there are obvious oscillating structure in the reaction probability.And as a typical system of heavy-light-light mass combination,this reaction is more conducive to the occurrence of product rotational excitation.Therefore,the product is mainly concentrated in the v'=0 and v'=1 states,and the rotational state distribution of the product rather than the vibrational state distribution appears the quantum number inversion phenomenon.In addition,due to the quantum interference of the rovibrational wave functions,the rotational state-resolved ICS has a multi-peak structure,and this phenomenon becomes less obvious as the collision energy increases.The total DCS peaked in the forward and backward directions,indicating a complex formation mechanism in the reaction.With the increase of the collision energy,the DCS changes from forward and backward scattering to forward scatteringWe also calculated the quantum state-to-state dynamics of the D+ND? N+D2 reaction on the 4A" PES,calculated and discussed the reaction probability,ICS and DCS.The results show that the rotational distribution,rather than the vibrational distribution,of the product has an obvious inversion.Due to the fact that it is a small-impact-parameter collision,the reaction is mainly controlled by the rebound mechanism,which can lead to the backward scattering at low collision energy.With the increase of the collision energy,the forward and sideward scattering appear and gradually increase.In addition,the backward scattering is also found to happen at high collision energy,which indicates that both the rebound mechanism and stripping mechanism exist at high collision energyFinally,the quantum state-to-state calculations have been implemented to study the dynamics of the S+(2D)+H,(X1?g+)?SH+(X3?-)+H(2S)reaction on the exact X2A" PES The obtained reaction probability,product state distribution and DCS show many characteristics of the abstraction reaction.Bcause of the presence of a deep potential well in the reaction,there are a lot of oscillating structures in the reaction probability.The total ICS is in good agreement with the previous quasi-classical trajectory result,which further verifies the accuracy of our calculation.In addition,the quantum number inversion occurred in the rotational distribution of the product,but there is no obvious vibrational inversion.This can be attributed to the heavy-light-heavy mass combination of the reaction,which is more effective for the product rotational excitation.In the range of collision energy considered,the DCS of the reaction is mainly concentrated in the forward and backward regions,which indicates that there is long life intermediate complex in the reaction process.