Polyacetylene Revisited: A Computational Study of the Molecular Engineering of N-type Polyacetylene

The development of stable and highly conductive polymers, particularly n-type materials, remains an outstanding challenge in organic electronics. N-doped polyacetylene has long been studied as a highly conductive organic n-type material but suffers from extremely poor stability. Herein, we use DFT to model a series of n-doped polyacetylene derivatives, which have been functionalized with a range of electron-withdrawing substituents, with the goal of identifying attractive candidates for synthesis. We analyze the predicted molecular orbital energies, polymer planarity, and delocalization of charge carriers along the polymer backbone. In so doing, we develop key insights about the ideal substituents for both stable and highly conductive polyacetylene derivatives. This work will inform the modern synthesis and development of new polyacetylene derivatives. Beyond this, the work identifies a variety of new materials that have not yet been synthesized and should be good candidates for emerging optoelectronic applications including soft thermoelectrics, bioelectronics, and flexible device technologies.