Evidence of lateral surface structure changes in transferred multilayer systems by electron microscopy

Abstract

Abstract:The substance-specific stability properties of transferred multilayer systems on germanium and quartz supports have been examined in the electron microscope. Typical micrographs with magnifications between 8 000 x and 40 000 x show that the surface structure of cadmium octadecanoate and octadecylammonium phosphate layer systems is dependent on the investigated parameters: type of substance, material of support, number of layers. Lateral structure rearrangement processes have been observed in the octadecanoate systems forming crystallites on both support materials and alllayer numbers. Similar irreversible transformations did not occur in transferred octadecylamine layer systems. The influence of the support material on the surface structure is interpreted as interaction differences between the support and the polar group of the first layer.

FTIR spectroscopic studies of layer systems transferred onto germanium supports

“…Using electron microscopy it was shown that within octadecylamine multilayers no irreversible transformations to three-dimensional crystals occur as it was found for octadecanoic acid multilayers [8]. The prevention of crystallization can be explained by the presence of free amine besides the corresponding alkylammonium compound.…”

“…Electron microscopy was used to obtain direct information about the lateral rearrangement process. It has been shown that layer systems of irregular structure and with three-dimensional crystallites are formed dependent on the material, the surface W 749 structure, and the polishing direction of the solid support [8]. Therefore, in the present paper a sensitive infrared ATR technique is proposed to study in simple systems the influence of the solid germanium support on the transferred layer system.…”

Die Herstellung von Amin- und Fetts�ure-LB-Schichten auf Quarzpl�ttchen sowie deren Homogenit�ts- und Stabilit�tspr�fung beim Kontakt mit Fl�ssigkeiten

“…Es muf~ deshalb die Schluf~folgerung gezogen werden, dat~ LB-Schichtsysteme, wie auch kiirzlich yon Vollhardt, Wittig und Mitarbeitern [10] best&igt wurde, nur unter besonderen, jeweils genau definierten Bedingungen in sich stabil sind, wenn sie in Kontakt mit anderen Fliissigkeiten kommen.…”