The N ₂I ₂(E0 _g ⁺) van der Waals complexes have been observed and studied for the first time. Analysis of the luminescence excitation spectra as well as luminescence spectra themselves in the spectral ranges, where the I ₂(D0 _u ⁺ → X0 _g ⁺, β1 _g → A1 _u and D'2 _g → A'2 _u) transitions can occur, has been carried out. Branching ratios of the iodine molecule state formation and vibronic level population have been determined. Ab initio calculations of the N ₂I ₂(X0 _g ⁺) complex ground state at complete basis set limit are performed. It is shown that it has two stable, parallel and linear, isomers separated by an energy barrier. The parallel isomer is observed in our experiments. Binding energies of the N ₂I ₂(X0 _g ⁺,v _X = 0,n _X = 0, B0 _u ⁺,v _B = 19,n _B = 0) as well as the some spectroscopic parameters of the N ₂I ₂(E,v _E = 0, 3) complexes have been also estimated.