Raman spectra of FeO, Fe3O4, α-Fe2O3, α-FeOOH, and γ-FeOOH, the common products of iron oxidation, have been measured. The spectra of FeO and Fe3O4 appear to be identical. Armco iron oxidized in air at 250°C was examined by Raman spectroscopy after varying periods of exposure and the surface film was found to contain Fe3O4 and α-Fe2O3.

The electrochemical reduction of α‐, γ‐, δ‐, and amorphous normalFeOOH was investigated. These oxides were applied as pastes to weathering steel substrates and galvanostatically reduced in solutions of 0.1MNa2SO4 . Raman and infrared spectroscopy were used to monitor the reaction products. Amorphous, γ‐,normaland δ‐normalFeOOH were reduced to magnetite, Fe3O4 , under the experimental conditions of this investigation; however, α‐normalFeOOH was not reduced under these conditions. The atmospheric corrosion product formed on a weathering steel light standard was entirely reduced to Fe3O4 and had a galvanostatic reduction curve similar to those for γ‐,normaland δ‐normalFeOOH .

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The use of Raman and infrared spectroscopy to analyze surface films on metals is described. Surface films formed on lead by reaction with aqueous buffer solutions were examined. The composition of each film was determined by Raman spectroscopy while the sample was in the solution. Multiple reflection infrared spectra of dry samples confirmed the Raman results. The Pourbaix diagram for lead in water was calculated, and potentiostatic exposures were conducted to see if the compounds corresponded to those predicted in the diagram. Tetragonal normalPbO was found to occur over a much greater range of potentials than thermodynamic stability would indicate.