Binary Iron−Dinitrogen Compounds Synthesized by Co-deposition of Mass-Selected Fe, Fe2, and Fe3 with N2

Iron−nitrogen binary complexes were synthesized by co-depositing mass-selected Fe+, Fe2+, and Fe3+ with N2 and electrons to form a matrix. The resulting compounds were observed using FTIR spectroscopy. The trigonal-bipyramidal Fe(N2)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(N2)x (x = 1 to 5) binary compounds. FTIR spectra of Fe2(N2)x and Fe3(N2)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.