ORIGIN OF STERIC HINDRANCE IN ETHANE

Steric hindrance has been regarded as a result of nonbonding atomic re pulsion and measured in terms of empirically obtained van der Waals ra dii. The authors sought the cause of steric hindrance using the partia l derivatives of the energy-components with respect to a nuclear coord inate. The results show that electrostatic interactions do not produce steric hindrance but the restriction on electron-movement does. Namel y, the kinetic energy pressure is the first cause of steric hindrance. (C) 1994 John Wiley & Sons, Inc