THEORY OF LONG-CHAIN MOLECULES WITH PARTIAL FLEXIBILITY

The conformation of a linear, semiflexible, long-chain molecule in a ⊖ solvent is described in terms of the theory of Markoffian processes due to Uhlenbeck and Ornstein. The model exhibits correct behavior in both the limiting cases of a completely flexible chain and a thin rigid rod, and gives a fair approximation to the wormlike chain at intermediate degrees of stiffness. In contrast to the wormlike chain, the present model permits analytical evaluation of all the higher moments of the end-to-end distance and thus offers a useful treatment of the angular distribution function for intensity of Rayleigh scattering. © 1969, American Chemical Society. All rights reserved.