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.
Institute for Experimental and Applied Physics, University of Regensburg, Regensburg, Germany. john.lupton@physik.uni-regensburg.de
John M
JM
Lupton