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The spatial distribution of electrons ejected by two-photon ionization of aromatic molecules was directly evaluated using a multi-layered structure of ultrathin polymer films where donor (D) and acceptor (A) layers were separated by spacing layers. The results show that electrons ejected by two-photon ionization are mostly captured by an A layer about 2–3 nm away from the D layer.

By bathing a smooth and highly [111]-oriented Ag film in a monomeric solution of pseudoisocyanine (1,1′-diethyl-2,2′-cyanine) bromide, we have found a uniform monolayer adsorption of self-assembled two-dimensional J-aggregate. A specific interaction of bromide ions with the Ag (111) surface seemed to be the major driving force for the dye adsorption. The system allows combined conventional spectroscopy and scanning tunneling microscopy studies of adsorbed J-aggregates of cyanine dyes.

Simple and well‐defined model AgX surfaces are useful to illuminate a variety of surface‐related phenomena associated with AgX microcrystals in a different perspective with fewer experimental impediments. From this viewpoint, we discuss a couple of pseudo‐AgX monolayers that can be organized on a highly planar sputter‐grown Ag(111) or ultrathin‐Au‐covered Ag(111) film. The monolayer structures have been satisfactorily characterized by combination of XPS and STM methods. In particular, the monolayer AgX formed on Au/Ag(111) proved to have an almost identical structure with the bilayer AgX(111) atomic configuration, thus serving as a superior monolayer model of AgX or pseudo 2D ionic crystal for deeper understanding of the processes involving the AgX surfaces. Microsc. Res. Tech. 42:100–107, 1998. © 1998 Wiley‐Liss, Inc.