Reactions of nitrogen oxides with heme models. Low temperature spectral characterization of the unstable nitratonitrosyl complex FeIII(TPP)(ONO2)(NO)

Reaction of NO gas with low temperature films of the (eta)2-nitrato model heme FeIII(TPP)(O2NO)(TPP =mesotetraphenylporphyrinato2–) leads to formation of the previously unknown (eta)1-nitrato nitrosyl species FeIII(TPP)(ONO2)(NO) as characterized by IR and optical spectroscopy with isotopically substituted nitrogen oxides.