How dual bridging atoms tune structural and optoelectronic properties of ladder-type heterotetracenes?-a theoretical study

Ladder-type heterotetracenes possessing fully ring-fused structures are a promising class of optoelectronic materials in terms of the lack of any conformational disorder, intense emission and high carrier mobility. To uncover how dual bridging atoms tune their structural and optoelectronic properties, the heterotetracenes were systematically investigated by theoretical calculations from several aspects, such as (i) the geometrical structures of ground and excited states; (ii) the highest occupied molecular orbitals (HOMO), the lowest unoccupied molecular orbitals (LUMO); (iii) ionization potentials (IP), electron affinities (EA), hole extraction potentials (HEP), electron extraction potentials (EEP), internal reorganization energies (lambda(int)) and transfer integrals (V); (iv) the absorption and emission spectra in vacuum and the dichloromethane (CH2Cl2) solvent, band gaps (E-g), excitation energies at the lowest singlet (E-S1) or triplet (E-T1) states as well as radiative lifetimes (tau). The theoretical investigations may be useful for finding new leading materials and are likely to provide important information for improving their photoelectric performance.