text: Consistent with Coulomb's law, There is a very strong relationship between the energetic stabilization associated with a sigma hole interaction and the product of the electrostatic potentials associated with the sigma hole and lone pair sites. Therefore, factors that increase the electrostatic potential of the sigma hole and decrease the electrostatic potential of the lone pair result in stronger interactions. The main structural factors contributing to the electrostatic potential of the sigma hole are the electronegativity of the host atom, the polarizability of the host atom, and the electron donating or withdrawing character of the group bonded to the host atom, with less electronegative and more polarizable host atoms bound to more electron withdrawing groups associated with the highest electrostatic potential.
  The table below shows the computed strength (in kcal/mol) of three selected sigma hole interactions at a variety of angles. At any angle, it can be observed that the interaction is stronger when the Bromine atom hosting the sigma hole is bound to a strongly electron withdrawing cyano group than when this atom is bound to a trifluoromethyl group, which is only moderately electron withdrawing. On the other hand, the interaction is stronger when an ammonia molecule provides the lone pair, as the electrostatic potential associated with this site is more negative than the corresponding site on hydrogen cyanide. In all cases, the interaction is becomes stronger at more linear angles.