Conformational characteristics of polymorphous optically active macromolecules: A statistical zigzag model

The conformational properties of optically active macromolecules are considered. A statistical zigzag model is used for the calculation of averaged physical properties. The macromolecule is considered to consist of segments of two different types with a statistical distribution of lengths. The expressions for the mean square of the end‐to‐end vector h 2 and the dipole moment μ 2 and also of the mean optical anisotropy Δ A and the anisotropy of the optical rotation tensor Δ G were obtained in the cases of freely jointed and freely rotating segments. The equations obtained were applied to the problem of the helix–coil transition. In the case of poly‐α‐olefins the values of h 2 , μ 2 , and Δ A , are larger than corresponding values for typical optically inactive macromolecules. The anisotropies Δ A and Δ G of two poly‐α‐olefins of similar structures were calculated. The polarizability theory of optical activity was used for the calculations of Δ G . The values obtained for Δ A are similar, but the values of Δ G differ markedly. The possibility of obtaining valuable information about the structure of optically active macromolecules in solution by a study of anisotropy of the optical rotation tensor is considered.