| We study the influence of structural obstacles in an environment on
the size and shape characteristics of long flexible polymer
macromolecules. We use the model of self-avoiding random walks on diluted
regular lattices with two types of disorder: long-range-correlated defects
and defects of critical concentration, when a fractal percolation cluster
emerges in the system. Applying the Pruned-Enriched Rosenbluth algorithm
(PERM), we estimate rotationally invariant universal quantities such as
the averaged asphericity and prolateness of polymer chain configurations.
Our results quantitatively reveal the extent of anisotropy of
macromolecules due to the presence of structural defects. |
