Electronic and Optical Properties of Conjugated Polymers, 3rd Edition

This book is a comprehensive theoretical treatise of the electronic and optical properties of conjugated polymers. There are three key goals for this book. The first is to build a theoretical understanding of how electron-electron interactions and electron-nuclear coupling determine the character and properties of the electronic states of conjugated polymers. Since these effects are complicated, the strategy is to start with the simplest approximation of noninteracting electrons and gradually develop the full description. At each step care is taken to explain how electron-electron interactions and electron-nuclear coupling modify the predictions of the simpler approximations. The concepts of the Peierls instability, soliton structures and excitons naturally emerge from this description.The second goal is to apply this understanding of the electronic states to two sets of exemplars of conjugated polymers, namely linear polyenes (in particular t-PA) and the light emitting polymers, PPP and PPV. It is shown that electronic states in t-PA are more strongly correlated than those in light emitting polymers, which explains the bright-dark state energy level reversal and the absence of luminescence t-PA.The final goal is to describe and explain electronic and optical processes in conjugated polymer systems, including energy and charge transport. To do this it is necessary to understand the role of conformational and environmental disorder. Disorder localizes charges and excitons, and determines their energetic and spatial distributions. In particular, disorder leads to the concept of a chromophore, whose size controls optical spectra and exciton diffusion. The fate of photoexcited states, from intrachain processes on femtosecond timescales, to interchain processes on picosecond timescales, is also explained.Electronic and Optical Properties of Conjugated Polymers is written for both experimentalists, and theoretical and computational researchers for whom there are a number of appendices containing material too technical for the main chapters. This new edition contains new topics on electronic and optical processes, especially spectroscopy, and energy and charge transport.