Production of N 3 upon Photolysis of Solid Nitrogen at 3 K with Synchrotron Radiation

The photodissociation of gaseous molecular nitrogen has been investigated intensively, but the corresponding knowledge in a solid phase is lacking. Irradiation of pure solid nitrogen at 3 K with vacuum‐ultraviolet light from a synchrotron produced infrared absorption lines of product l ‐N 3 at 1657.8 and 1652.6 cm −1 . The threshold wavelength to generate l ‐N 3 was determined to be (143.7±1.8) nm, corresponding to an energy of (8.63±0.11) eV. Quantum‐chemical calculations support the formation of l ‐N 3 from the reaction N 2 +N 2 , possibly through an activated complex l ‐N 4 upon photoexcitation with energy above 8.63 eV. The results provide a possible application to an understanding of the nitrogen cycle in astronomical environments.