Controlling Growth to One Dimension in Nanoislands of Ferrocene-Sugar Derivatives

Abstract

Ferrocenyl-Alkyl-Protected Sugar (Fc-Sug) and Ferrocenyl-Oxo-Alkyl-Protected Sugar (Fc-Oxo-Sug) were deposited on the basal plane of Highly Oriented Pyrolytic Graphite (HOPG) using a drop-casting method. Ultrathin films of these molecules were investigated using Atomic Force Microscopy to understand the growth at low coverage. Both molecules are forming highly ordered one-dimensional molecular islands, which are growing from a dimer building block. The dimer and interdimer interactions (along the length of islands) are stabilized by −C2O···H–C hydrogen bonding. Unlike for Fc-Sug, the islands of Fc-Oxo-Sug are extended to tens of micrometers, and the growth is only limited by terrace edges or other islands on the surface. This exceptional growth of islands is understood in terms of an additional −CO···H–C– hydrogen bonding leading to stronger interdimer interactions along the length of the islands compared to Fc-Sug.

On‐Surface Synthesis of Polyferrocenylene and its Single‐Chain Conformational and Electrical Transport Properties

“…[56] There have been several studies on adsorption of metallocenes and metallocene-based molecules and their formation on various surfaces. [52,54,[57][58][59] Ferrocene molecules have been investigated in more detail both experimentally [60][61][62][63][64][65][66][67] and theoretically, [52,68,69] focusing on their orientation on the substrate and interaction with it rather than their on-surface reactivity.…”

Solvent‐ and Temperature‐Dependent Assembly in Monolayer Films of a Ferrocene‐Naphthyridine Hybrid on HOPG

“…The pairs indicate mirror domains and the long edge of the molecular islands are rotated by~� 4°with respect to the compact lattice directions of graphite. [14,22] Occasionally, we have also observed islands oriented at~30°, 90°and 150°i ndicating their orientation along the next nearest compact lattice directions of graphite. The apparent height of the molecular islands is consistent with monolayer films of nonplanar molecules.…”

“…[13] Fc functionalized with bulky groups are used to control the patterns of the monolayer at the solid-air interface. [14] Solvent has been a choice in controlling the quality and microscopic nature of molecular films. The microscopic arrangement of Fc derivatives is controlled at different types of solid-liquid interfaces.…”

“…Under mild annealing temperatures, it is demonstrated that the molecular patterns in the monolayer on surface can be controlled [13] . Fc functionalized with bulky groups are used to control the patterns of the monolayer at the solid‐air interface [14] . Solvent has been a choice in controlling the quality and microscopic nature of molecular films.…”

Ferrocenes as Building Blocks in Molecular Rectifiers and Diodes

“…In particular, ferrocene-terminated alkane thiolates have been particularly well studied whereas ferrocenes with silane, carboxylate, and phosphonate linker groups have not been investigated in as much detail. Interestingly, ferrocenyl alkane chains that have sugar termini have also recently been reported but rectification behavior of electrodes that contain those molecules has not [ 38 ]. Ferrocene is particularly useful for work in this field since its HOMO is close in energy to the Fermi levels of typically used electrodes.…”