Abstract
The collision energy dependence of cross-section for reactions where the reactants attract is discussed. Examples include charge recombination A+ + B- → products, ion-molecule reactions and other curve crossing processes. The common characteristic of such processes is that on physical grounds there is a critical distance d where capture occurs. Special attention is given to the case where the critical separation is independent of energy and/or impact parameter. A modern example where this is the case is laser-induced association of atoms. The capture cross-section has the functional form σ = πd2(1 - Vg(d)/ET) where for the collisions discussed the potential is attractive, Vg(d) < 0. Such a cross-section is a decreasing function of the collision energy ET. The same functional form is also useful if the potential is repulsive, Vg(d) > 0. For this well-known case, the cross-section is an increasing function of the collision energy.
Original language | English |
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Pages (from-to) | 129-132 |
Number of pages | 4 |
Journal | Chemical Physics |
Volume | 270 |
Issue number | 1 |
DOIs | |
State | Published - 15 Jul 2001 |