Elucidating Surface Structure with Action Spectroscopy

摘要

Surface Action Spectroscopy, a vibrational spectroscopy method developed in recent years at the Fritz Haber Institute is employed for structure determination of clean and H_2O-dosed (111) magnetite surfaces. Surface structural information is revealed by using the microscopic surface vibrations as a fingerprint of the surface structure. Such vibrations involve just the topmost atomic layers, and therefore the structural information is truly surface related. Our results strongly support the view that regular Fe_3O_4(111)/Pt(111) is terminated by the so-called Fe_(tetl) termination, that the biphase termination of Fe_3O_4(111)/Pt(111) consists of FeO and Fe_3O_4(111) terminated areas, and we show that the method can differentiate between different water structures in H_2O-derived adsorbate layers on Fe_3O_4(111)/Pt(111). With this, we conclude that the method is a capable new member in the set of techniques providing crucial information to elucidate surface structures. The method does not rely on translational symmetry and can therefore also be applied to systems which are not well ordered. Even an application to rough surfaces is possible.