Non-covalent forces drive spontaneous folding of proteins and nucleic acids and mediate recognition of complementary molecular surfaces. Noncovalent forces were discovered by van der Waals during analysis of deviations from the ideal gas law.
Noncovalent forces dictate conformation and interaction in biological systems.
Unfortunately these forces are complex and remain poorly understood. It is necessary to understand delicate balances among powerful countervailing forces. There are many different ways of classifying noncovalent interactions. Each of these is fundamentally electrostatic in nature and can described by Coulombs Law. Because this repulsive term rises so sharply as distance decreases it is reasonable to think of atoms as hard spheres defined by van der Waals radii.