Collision dynamics theory

Let us compare these results with the predictions of the theory formulated by Lampe etal. (24) in terms of a steady-state concentration of collision complexes. This is a classical macroscopic treatment insofar as it makes no assumptions about the collision dynamics, but its postulate of collision complexes implies that v8 = vp/2 for the system treated above. Thus, its predictions might be expected to coincide with those of the collision-complex model. Figure 3 shows that this is not so the points calculated from the steady-state theory (Ref. 25, Equation 10) coincide exactly with the curve for which v8 = vv. The reason for this is that the steady-state treatment assumes a constant time available for reaction irrespective oC the number of reactions occurring in any one reaction... 

Zimm theory, multiparticle collision dynamics, polymers, 123-124... 

Experiments have also played a critical role in the development of potential energy surfaces and reaction dynamics. In the earliest days of quantum chemistry, experimentally determined thermal rate constants were available to test and improve dynamical theories. Much more detailed information can now be obtained by experimental measurement. Today experimentalists routinely use molecular beam and laser techniques to examine how reaction cross-sections depend upon collision energies, the states of the reactants and products, and scattering angles. 

Having recognized the close quantitative connection between optical properties and collision dynamics at this stage of development of atomic theory is a remarkable example of Bohr s physical intuition. 

The theory of molecular scattering has now been developed to the point that scattering calculations can be made with an accuracy sufficient for comparison with current experiments. Thus any discrepancy between theory and experiment should be traced to an inadequate knowledge of the interaction potentials, or to experimental errors, rather than to approximations in the collision dynamics. This tighter coupling of theory and experiment should permit a much more fruitful utilization of the results of molecular beam scattering. 

In this chapter we summarize the current status of the low-energy scattering of noble-gas metastable atoms in molecular beams. A brief summary of potential scattering theory that is relevant to the understanding of collision dynamics, as well as a description of the experimental method, precedes the presentation of experimental findings. The experimental results presented are mainly from the authors laboratories. 

J. Cl. Maxwell [l] Illustrations of the dynamical theory of gases, Part 1 On the motions and collisions of perfectly elastic spheres, Phil. mag. (4) 19 (1860), p. 19 Part 2 On the process of diffusions of two or more kinds of moving particles among one another, Phil. Mag. (4) 20 (1860), p. 1 (also Scientific Papers 1, Cambridge 1890, p. 377). 

The isolated binary collision (IBC) theory is one of the earliest dephasing theories developed for liquids (77). Despite criticism of its assumptions (78), it remains popular for the interpretation of experimental data, because it relates the dephasing to easily measurable solvent properties. It assumes that the solvent dynamics are essentially gas-like, consisting of uncorrelated collisions of the vibrating molecule with solvent molecules. The solvent-solute interaction is taken as purely repulsive. The dependence of... 

Maxwell JC (1860) lUnstrations of the Dynamical Theory of gases. - Part I. On the Motions and Collisions of Perfectly Elastic Spheres. Phil Mag 19 19-32 Maxwell JC (1867) On the Dynamical Theory of gases. Phil Trans Roy Soc London 157 49-88... 

We present here a summary of our work on the collision dynamics of three Interacting atoms, (O adding new developments on the theory of resonances in rearrangement collisions. We begin by showing how to go from a description In terms of electrons and nuclei to one... 

From Ligand Field Theory to Molecular Collision Dynamics A Common Thread of Angular Momentum... 

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