RESUMEN
Charge transfer (CT) crystals exhibit unique electronic and magnetic properties with interesting applications. We present a rational and easy guide which allows to foresee the effective charge transfer co-crystal production and that is based on the comparison of the frontier molecular orbital (MO) energies of a donor and acceptor couple. For the sake of comparison, theoretical calculations have been carried out by using the cheap and fast PM6 semiempirical Hamiltonian and pure HF/cc-pVTZ level of the theory. The results are then compared with experimental results obtained both by chemical (bromine and iodine were used as the acceptor) and electrochemical doping (exploiting an original experimental set-up by this laboratory: the electrochemical transistor). Infra-red vibrational experimental results and theoretically calculated spectra are compared to assess both the effective donor-acceptor (D/A) charge-transfer and transport mechanism (giant IRAV polaron signature). XPS spectra have been collected (carbon (1â s) and iodine (3d5/2)) signals, yielding further evidence of the effective formation of the CT anthracene:iodine complex.
RESUMEN
Both aryl and benzyl polybromides have gained significant importance as reactive building blocks in polymer and materials chemistry. Their preparation primarily relies on established synthetic methods using molecular bromine or N-bromosuccinimide, known for their reliability and effectiveness. However, from a sustainability perspective, these methods suffer from the generation of stoichiometric amounts of byproducts and often encounter selectivity troubles. To mitigate these issues, we extended the greener peroxide-bromide halogenation method, initially developed for monobromides, to afford aryl-cored polybromides in high yields. The same method can be employed in two variants modulated by light irradiation. This external switch can be used to selectively trigger side-chain or core halogenation.