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

Abstract

The formation of a monolayer film of bis-naphthyridyl ferrocene on highly oriented pyrolytic graphite (HOPG) at ambient conditions is demonstrated. The films are prepared by drop casting from different solvents. The microscopic structure of the films is understood using atomic force microscopy (AFM) and scanning tunnelling microscopy (STM). The analysis reveals two different types of Phases (I and II) in the films and the relative percentage of these phases depends on the nature of the solvents used for the preparation and the thermodynamical condition. Solvents like methanol, acetonitrile and DMF exclusively select Phase-I, whereas acetone and ethanol show a mix of both phases at room temperature. The different phases are formed by different conformers of the molecule. We also show that the selectivity of one of the phases over the other is related to the difference in the energetics for the formation of these phases.

Defect-engineered surfaces to investigate the formation of self-assembled molecular networks

“…when self-assembly on pristine and chemically modied substrates differs qualitatively. [39][40][41] No QZ-C16 self-assembly was observed on bare HOPG at or below 10 −6 M (Scheme 1c), while closepacked domains of QZ-C16 could be visualized on CM-HOPG even at 5 × 10 −7 M (Scheme 1d and e). Fully controlling the surface density of such covalently bound aryl pins empowers advanced investigation and control of various interfacial processes.…”