In the present study, the equilibrium structures, binding energies, and the nature of the coupling interactions in H2SO4⋯HNO⋯(H2O)n (n = 0–2) clusters have been systematically investigated at the MP2/aug-cc-pVDZ level of theory in combination with the atoms in molecules (AIM) theory and many-body interaction energies. Particular attention is given to existence and magnitude of NH⋯O blue-shifting hydrogen bonds (H-bonds). It was found that the insert of one or two water molecules can efficiently enhance the interactions between H2SO4 and HNO, pointing the positive role of water molecules in the uptake of the HNO via sulfuric acid aerosols. Based on the energy decomposition analysis (EDA), it can be seen that the stabilities of the clusters are predicted to be attributable mainly to electrostatic and polarization effects.
