Orbital collisions (kinetics)
An example of orbital orientation at point of collision (see: collision theory) as an aspect of the "kinetic factor" in chemical reactions; namely above: molecular orbitals are aligned, at collision point, in such a way that orbital A and orbital B both make contact, therein allowing the products AB and AB to form; below: molecular orbitals are misaligned at collision point, such that only one orbital A and one orbital B make contact, and no products are formed, i.e. no chemical reaction occurs, only an inelastic collision occurs. [1]
In physical chemistry, kinetic factor refers to the finding that in order for two chemical entities to react, they must not only have the correct “thermodynamic factor”, i.e. form stable end state products, as determined by the free energy change of the reaction, but also have the correct collisional energy (see: collision theory) or kinetic energy, i.e. right trajectory, bond orientation, and reactant concentration, in order to get over the activation energy barrier. [1]

The following are related quotes:

“If you have chemistry, you only need one other thing. Timing. But timing’s a bitƈh.”
— Anon (c.2010), Internet (Ѻ) meme

1. Thims, Libb. (2007). Human Chemistry (Volume One) (pdf) (§: Collision Theory, pgs. 98-103; orbital orientation and kinetics, pgs. 280-83). Morrisville, NC: LuLu.

Further reading
● Keseru, Gyorgy. (2015). Thermodynamics and Kinetics of Drug Binding (editors: David Swinney, Raimund Mannhold, Hugo Kubinyi, Gerd Folkers). Wiley.

External links
Chemical kinetics – Wikipedia.
Kinetic and thermodynamic control – University of Calgary.

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