Modeling Born repulsive and van der Waals forces

Intermolecular (or interatomic) potentials characterized by short-range (Bom) repulsive forces and longer range (van der Waals) attractive forces are often mathematically modeled using the so-called Mie potential expression 

The L-J model is a good representation for intermolecular interactions involving electrically neutral, nonpolar, and short/compact-shaped molecules. A short list of the popular L-J (6-12) potential (p = 6, q = 12) constants for various substances is given in Table 1.1. Note that the value of 7 = 2p is selected primarily because it gives a decent fit of the experimental data and makes the algebra of the fitting exercise simpler. 

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