Stereochemical investigations. XXXV. Van der Waals interactions as the reason for conformational characteristics. Treatment of the data from molecular mechanics by the method of preoptimum structures

An approach to the analysis of the data from molecular mechanics is developed which makes it possible to overcome one of the main difficulties of the method in that the interdependence of the various components of the steric energy frequently leads to the impossibility of establishing a specific reason for the relative instability of one or other conformation of an organic molecule. The proposed method of model calculation (with the use of molecular mechanics) makes it possible to concentrate the various intramolecular stresses in the form of van der Waals interactions, which are readily amenable to interpretation in terms of the classical concepts of conformational analysis