Abstract
The quantum-mechanical equations of motion for collision can be solved numerically, at least for rigid rotors, at low enough energy so that only a small number of channels are accessible. Such solutions are expensive and limited to the simplest systems. For practical solutions of collision problems one must resort to various approximations. In recent years a number of excellent approximations for rotational excitation have become available. The approximations to the fully quantal collision problem for rotational scattering are usually based on the time-independent formulation of the problem. The full quantum-mechanical equation for the collision of two rotors given in this chapter serves as a starting point for the various approximations to the quantum-mechanical treatment of rotational energy transfer. The close-coupling equations are of course the most accurate approximation to the collision problem and appear to give answers to any desired accuracy if enough terms are carried in the expansion. The close-coupling equations have the same form as that taken by almost all of the quantal approximations, and as a result the techniques used to solve the close-coupling equations are well suited to solving most systems of coupled second-order differential equations which arise in time-independent quantum scattering problems.
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R.T Pack, private communication.
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© 1979 Plenum Press, New York
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Secrest, D. (1979). Rotational Excitation I: The Quantal Treatment. In: Bernstein, R.B. (eds) Atom - Molecule Collision Theory. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-2913-8_8
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DOI: https://doi.org/10.1007/978-1-4613-2913-8_8
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