The interaction between NO2+ cation and Hen (n=1-7) clusters is investigated by means of ab initio calculations at MP2/aug-cc-pVTZ and QCISD/aug-cc-pVTZ levels. Stabilization energy of studied complexes including BSSE and ZPE corrections at MP2/aug-cc-pVTZ computational level are in the range of 1.5–7.6 kJ/mol. There is a good linear correlation between the stabilization energy and blue shift of symmetric and asymmetric stretching frequencies of NO2+ in the studied complexes. Energy decomposition analysis shows that polarization effects are the main source of the attraction energy in these complexes. The second most important attraction term is dispersion energy.
