Planar Supramolecular Systems: Assembly and Functional Potential

In this review, we present one of the main areas of the work of the Laboratory of Physical Chemistry of Supramolecular Systems, Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, devoted to studying monolayers and ultrathin films on liquid and solid surfaces. Numerous problems are discussed concerning the peculiarities of the supramolecular organization, behavior, and functional potential of these traditional colloidal systems. The article describes diverse examples of systems that form ultrathin organized films at different interfaces and the processes occurring in them, thereby reflecting the contemporary stage of the interconnection of related fields of science (colloid and supramolecular chemistry, nanotechnology, biomimetics, sensorics, etc.). Such a combination makes it possible to develop new intelligent nanostructured devices. Complexation in ultrathin layers of ligands on liquid and solid substrates is considered in connection with the use thereof as sensitive sensory elements in systems with reduced dimensionality. Substantial attention is focused on the aggregation behavior of diverse ligands and topochemical reactions in organized 2D ensembles, development of new methods for preparing two-dimensional organic networks, and creation of highly stable supramolecular devices based thereon. In the light of the features of 2D systems, several types of mechanochemical transformations occurring under the action of two-dimensional compression-expansion are considered: the phenomenon of redox isomerism in monolayers of lanthanide bis-phthalocyaninates, the phenomenon of forced axial coordination in tetrapyrrole complexes of nickel with a change in its spin number, and the phenomenon of the reversible formation of excimers. Especial attention is given to the problems concerning the behavior of organic photochromes at interfaces and the perspectives of developing molecular switches based on photosensitive compounds.

Automated summary

This review presents the main research area of the Laboratory of Physical Chemistry of Supramolecular Systems at the Frumkin Institute of Physical Chemistry and Electrochemistry, focusing on monolayers and ultrathin films on liquid and solid surfaces. The article discusses the peculiarities of supramolecular organization, behavior, and functional potential of these systems, providing examples of systems forming ultrathin organized films and processes occurring at different interfaces.