Density functional calculation of the infrared spectrum of surface hydroxyl groups on goethite (α-FeOOH)

We present density functional calculations of vibrational frequencies of OH groups on all idealized goethite (110) surface. represented by a large embedded cluster model. The calculations show that isolated surface groups bound to one. two and three metal ions can have nearly identical OH stretching frequencies. This finding provides a strong constraint oil interpretations of infrared spectra of oxide surfaces. and resolves a long-standing problem in OH vibrational assignments oil goethite surfaces. where, in general, too few peaks have been observed relative to the expected heterogeneity of surface Functional groups.