Intramolecular interactions in molecular mechanics calculations

Abstract Some applications of quantum chemical calculations in studying intramolecular potentials are considered. The nature of the bond angle bending function is shown to be different for the small rings, cyclopropane and cyclobutane, than for other alicyclic compounds. The magnitudes of the CH bond dipoles are shown to be larger than commonly assumed and to be dependent on hybridization. The Coulombic interactions between the atomic charges is an important component of the interaction energy. Quantum chemical calculations also have a real potential for determining the angular dependence of non-bonded interactions.

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