Multi-layer Gaussian-based multi-configuration time-dependent Hartree (ML-GMCTDH) simulations of ultrafast charge separation in a donor–acceptor complex

We report on first applications of the Multi-Layer Gaussian-based Multi-Configuration Time-Dependent Hartree (ML-GMCTDH) method [Römer et al., J. Chem. Phys. 138, 064106 (2013)] beyond its basic two-layer variant. The ML-GMCTDH scheme provides an embedding a variationally evolving Gaussian wavepacket basis into hierarchical tensor representation wavefunction. A first-principles parameterized model Hamiltonian for ultrafast non-adiabatic dynamics in oligothiophene–fullerene charge transfer complex is employed, relying two-state linear vibronic coupling that combines distribution tuning type modes with intermolecular coordinate also modulates electronic coupling. Efficient simulations are carried out up to 300 vibrational using implementation within QUANTICS program. Excellent agreement reference ML-MCTDH calculations obtained.