Iron-nitrogen binary complexes were synthesized by co-depositing mass-selected Fe+, Fa(2)(+), and Fe-3(+) with N-2 and electrons to form a matrix. The resulting compounds were observed using FTIR spectroscopy. The trigonal-bipyramidal Fe(N-2)(5) structure assigned from the spectra of the Fe+ deposits is supported by density functional calculations involving full geometry optimizations with all symmetry conditions relaxed for Fe(N-2)(x) (x = 1 to 5) binary compounds. FTIR spectra of Fe-2(N-2)(x) and Fe-3(N-2)(y) are also reported. Structures for the dimer and trimer dinitrogen complexes have not been deduced since the spectra are too weak to perform isotopic substitution experiments.