Results of the joint experimental and computational studies of structural features, bonding and thermodynamic properties of molecular complexes of iodine with bidentate nonchelated N-containing donors pyrazine and 4,4′-bipyridine are reported. Irrespective of the starting ratio of the components, complexes of 2:1 composition are predominantly formed in the solid state. Molecular structures of new molecular complex of I2 with pyrazine and a new polymorph of complex of 4,4′-bipyridine of 2:1 composition have been determined by single crystal structural analysis. In both complexes, ligand serves as bifunctional donor connecting two molecules of I2. All I[sbnd]N distances are shorter than the sum of van der Waals radii and the I-I-N angles are close to 180°. To reveal the stability of the complexes of different compositions and the nature of N[sbnd]I bond, the DFT computations were performed. Stability and volatility of compounds upon heating in vacuum were studied using static tensimetry method with membrane null-manometer. Thermodynamic characteristics of the complex dissociation processes were estimated.