Charge-transfer excitations in molecular donor-acceptor complexes within the many-body Bethe-Salpeter approach

Xavier Blase (1) , Claudio Attaccalite (1)

1 NEEL - TMC - Théorie de la Matière Condensée

We study within the perturbative many-body $GW$ and Bethe-Salpeter approach the low lying singlet charge-transfer excitations in molecular donor-acceptor complexes associating benzene, naphtalene and anthracene derivatives with the tetracyanoethylene acceptor. Our calculations demonstrate that such techniques can reproduce the experimental data with a mean average error of 0.1-0.15 eV for the present set of dimers, in excellent agreement with the best time-dependent density functional studies with optimized range-separated functionals. The present results pave the way to the study of photoinduced charge transfer processes in photovoltaic devices with a parameter-free \textit{ab initio} approach showing equivalent accuracy for finite and extended systems.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Xavier Blase, Claudio Attaccalite. Charge-transfer excitations in molecular donor-acceptor complexes within the many-body Bethe-Salpeter approach. Applied Physics Letters, 2011, 99 (17), pp.171909. ⟨10.1063/1.3655352⟩. ⟨hal-00626221⟩