Chromophores in Conjugated Polymers—All Straight?

What is the physical shape of the π-electron system in a large macromolecule such as a conjugated polymer? Although intuitively one may argue that any departure from rigidity by bending or twisting should disrupt conjugation, leading to the formation of discrete chromophores, single-molecule and ensemble time-resolved studies support the notion that the π-bond is remarkably persistent in space: even individual chromophores can be bent and twisted, so that caution is warranted when interpreting a wide range of polarisation-based spectroscopies.