The attraction between π-conjugated planar electron donor and acceptor molecules within charge–transfer (CT) complexes has been explained by quantum chemical CT interactions, but its fundamental origins remain unclear. Here, the authors combine symmetry-adapted perturbation theory with coupled cluster calculations to probe the mechanism of CT complex formation in crystals, finding that dispersion and electrostatic forces are dominant, with significant directional exchange repulsion.
- Seiji Tsuzuki
- Ryota Ono
- Tatsuo Hasegawa
