A Singularity Model for Chemical Reactivity

This article proposes a model for chemical reactivity that involves singularities (“catastrophes”) in the timing of bond‐making and bond‐breaking events. The common stapler is a good mechanical analogy: As hand‐pressure is increased on the machine, the staple hardly changes its configuration until the staple suddenly bends. This is viewed as a singularity or catastrophe, defined classically as an abrupt change resulting from a smooth increase or decrease in external conditions (pressure in the case of a stapler, distance in the case of reactivity). Although experimental observations are provided to support the singularity effect, the model remains a heterodox notion at the present time.