title: Synthesis and Characterization of Cyclopentadithiophene Heterofulvenes: Design Tools for Light-Activated Processes.
abstract: The development of new materials for solar-to-energy conversion should consider stability, ease of fabrication, and beneficial photophysical properties. In this context, a set of novel π-conjugated building blocks, with phospha- and arsaalkenes possessing a unique dithienyl annulated heterofulvenoid core, have been prepared as air- and moisture-stable sensitizers. These compounds unify electron-donor and -acceptor moieties, making them potential candidates for light-harvesting applications. Optical characterization of these systems was performed by steady-state and time-resolved absorption spectroscopy, supported by time-dependent DFT calculations. Tuning of the optical properties of these systems can be achieved by varying the pnictogen element at the bridgehead position, giving a bathochromic shift of ≈40 nm and coordinating the phosphaalkene towards gold AuIcenters. The latter results in a ≈2000-fold extension of the ≈10 ps lifetime of uncoordinated systems well into the ns regime.
authors.affiliation: Chemical Physics Department, Lund University, Sweden.
authors.forename: Amal
authors.identifier: http://orcid.org/0000-0002-4723-319X
authors.initials: A
authors.lastname: El Nahhas
authors.affiliation: Department of Chemistry-Ångström laboratories, Uppsala University, Sweden.
authors.forename: Muhammad Anwar
authors.initials: MA
authors.lastname: Shameem
authors.affiliation: Chemical Physics Department, Lund University, Sweden.
authors.forename: Pavel
authors.identifier: http://orcid.org/0000-0002-0531-5138
authors.initials: P
authors.lastname: Chabera
authors.affiliation: Chemical Physics Department, Lund University, Sweden.
authors.forename: Jens
authors.identifier: http://orcid.org/0000-0002-0528-0422
authors.initials: J
authors.lastname: Uhlig
authors.affiliation: Department of Chemistry-Ångström laboratories, Uppsala University, Sweden.
authors.forename: Andreas
authors.identifier: http://orcid.org/0000-0001-5403-9902
authors.initials: A
authors.lastname: Orthaber
keywords: arsaalkene; electrochemistry; main group elements; phosphaalkene; pnictogens; time-resolved spectroscopy