ABSTRACT
The Rotational Isomeric State (RIS) model is excellent for the analysis of conformationdependent physical properties of chain molecules in their unperturbed state. Its special strength is the incorporation of detailed information about the covalent structure (bond lengths, bond angles, torsion angles, and torsion potential energy functions) in a formalism that can be evaluated quickly by the smallest computer. The answer is the exact result for the specific model, as defined by the geometry and energies of the shortrange intramolecular interactions.
