Deformation, Stretching, and Relaxation of Single‐Polymer Chains: Fundamentals and Examples#

We review the basic theory for the static and dynamic properties of ideal and real chains. We describe the stretching of single ideal chains in both the strain and the stress ensembles, give scaling arguments for the deformation of real chains, and also consider the impact of chain rigidity by discussing the stretching of worm-like chains. We complement this theoretical outlook with specific examples that highlight the relevance of the single-molecule deformation in a practical perspective: the translocation of a macromolecule over a potential barrier, the collision of a single chain with fixed obstacles or other chains, the dynamics of a thethered chain in a strong shear flow, and some remarkable predictions concerning the deformation of composite chain molecules during free-solution electrophoresis.