Quantum reactive scattering

Schatz G C and Kuppermann A 1975 Quantum mechanical reactive scattering an accurate three-dimensional calculation J. Chem. Phys. 62 2502... 

Colbert D T and Miller W H 1992 A novel discrete variable representation for quantum mechanical reactive scattering via the S-matrix Kohn method J. Chem. Phys. 96 1982... 

The F + H2 — HF + FI reaction is one of the most studied chemical reactions in science, and interest in this reaction dates back to the discovery of the chemical laser.79 In the early 1970s, a collinear quantum scattering treatment of the reaction predicted the existence of isolated resonances.80 Subsequent theoretical investigations, using various dynamical approximations on several different potential energy surfaces (PESs), essentially all confirmed this prediction. The term resonance in this context refers to a transient metastable species produced as the reaction occurs. Transient intermediates are well known in many kinds of atomic and molecular processes, as well as in nuclear and particle physics.81 What makes reactive resonances unique is that they are not necessarily associated with trapping... 

In addition to experiments, a range of theoretical techniques are available to calculate thermochemical information and reaction rates for homogeneous gas-phase reactions. These techniques include ab initio electronic structure calculations and semi-empirical approximations, transition state theory, RRKM theory, quantum mechanical reactive scattering, and the classical trajectory approach. Although still computationally intensive, such techniques have proved themselves useful in calculating gas-phase reaction energies, pathways, and rates. Some of the same approaches have been applied to surface kinetics and thermochemistry but with necessarily much less rigor. 

G.C. Schatz, A. Kuppermann, Dynamical resonances in collinear, coplanar, and three-dimensional quantum mechanical reactive scattering, Phys. Rev. Lett. 35 (1975) 1266. 

R.S. Freidman, D.G. Truhlar, Barrier resonances and chemical reactivity, in D.G. Truhlar, B. Simon, (Eds.), Multiparticle Quantum Scattering with Applications to Nuclear, Atomic, and Molecular Physics, Springer-Verlag, New York, 1997, p. 243. 

Miller, W.H. (1990). Recent advances in quantum mechanical reactive scattering theory, including comparison of recent experiments with rigorous calculations of state-to-state cross sections for the H/D + H2 —> H2/HD + H reactions, Ann. Rev. Phys. Chem. 41, 245-281. 

Quantum Mechanical Reactive Scattering Using a High-Performance Distributed-Memory Parallel Computer. 

In the quantum scattering approach the collision is modelled as a plane wave scattering off a force field which will in general not be isotropic. Incident and scattered waves interfere to give an overall steady state wavefunction from which bimolecular reaction cross-sections, cr, can be obtained. The characteristics of the incident wave are determined from the conditions of the collision and in general the reaction cross-section will be a function of the centre of mass collision velocity, u, and such internal quantum numbers that define the states of the colliding fragments, represented here as v and j. Once the reactive cross-sections are known the state specific rate coefficient, can be determined from. 

Schatz, G. C. and Kuppermann, A. (1976) Quantum mechanical reactive scattering for three-dimensional atom plus diatom systems. I. Theory, J. Chem. Phys. 65, 4642-67. 

Hankel, XL, Balint-Kurti, G.G. and Gray, S.K. (2003) Sine wavepackets A new form of wavepacket for rime-dependent quantum mechanical reactive scattering calculations Int. J. Quant. Cham. 92, 205-211. 

We focus attention on both the theory of rates and the electronic mechanism for generic chemical processes. An exact quantum mechanical transition state theory was early developed by Miller [18] and rate expressions were derived from quantum scattering theory [19]. That approach and subsequent developments are based upon the reactive BO potential energy surfaces where the familiar case concerns a reaction accompanied by a smooth change in the overall electronic energy surface [20], The R-BO approach does not have such adiabatic changes of electronic states and it is of interest to see the way quantum scattering theory handles the problem in this new context. 

W.H. Miller, Recent advances in quantum mechanical reactive scattering theory, Annu. Rev. Phys. Chem., 41 (1990) 245-281. 

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