Behavior of Kinks

The motion of a single kink is analogous with an embedded chemical reaction of the simple exchange type (Gilman, 1993). A pair of atoms, above and below the glide plane exchange partners when a kink moves a unit b amount. 

This is analogous with the classic chemical reaction in which hydrogen and deuterium exchange during a collision  

Here the energies of the reactants AC and B are linked (correlated) with the products, CB and A across the reaction space (reaction coordinate). When x = b/2, the three atoms form a transition complex, ACB. 

Chemical bonds are defined by their frontier orbitals. That is, by the highest molecular orbital that is occupied by electrons (HOMO), and the lowest unoccupied molecular orbital (LUMO). These are analogous with the top of the valence band and the bottom of the conduction band in electron band theory. However, since kinks are localized and non-periodic, band theory is not appropriate for this discussion. 

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