Energy decomposition analysis methods for intermolecular interactions with excited states

Intermolecular interactions with excited states play important roles in various photochemical and photophysical processes. In this work, an energy decomposition analysis (EDA) method of intermolecular interactions for systems in which one monomer is in a singly excited state while others are in their ground states, called GKS-EDA(TD), is proposed. Based on the computational results of time-dependent density functional theory (TD-DFT), GKS-EDA(TD) divides the total interaction energy with excited states into electrostatic, exchange-repulsion, polarization, correlation and dispersion. The nature of intermolecular interactions in test examples with their low-lying singly excited states is investigated, which shows that GKS-EDA(TD) can be used for various intermolecular interactions with different excitation modes. Furthermore, GKS-EDA(TD) is employed to explore the non-covalent interactions in a series of C60MIDLINE HORIZONTAL ELLIPSIS nucleic acid base complexes with the decomposition of excitation energy contribution.

Automated summary

In this study, a new energy decomposition analysis method called GKS-EDA(TD) is proposed to investigate intermolecular interactions in systems where one monomer is in a singly excited state and others are in their ground states. Based on computational results, GKS-EDA(TD) divides the total interaction energy with excited states into several components. The method is applied to explore intermolecular interactions and excitation energy contribution in C60 nucleic acid base complexes.