Solvent‐ and Temperature‐Dependent Assembly in Monolayer Films of a Ferrocene‐Naphthyridine Hybrid on HOPG. Issue 11 (29th April 2021)

• Record Type: Journal Article
• Authors: Malik, Himani; Saha, Prithwidip; Patra, Kamaless; Bera, Jitendra K.; Gopakumar, Thiruvancheril G.
• Is Part Of: Chemistry, an Asian journal. Volume 16:Issue 11(2021)
• Page Start: 1430
• Page End: 1437
• Publication Date: 2021-04-29
• Subjects: Solvent Dependent Assembly -- Molecular Thin-Films -- Ferrocene Assembly -- Scanning Probe Microscopy; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/asia.202100187
• Languages: English
• ISSNs: 1861-4728

Abstract

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. Abstract : The electronic property of thin films is directly related to the microscopic arrangement of the molecule within the film. Therefore, controlling their assembly or microscopic structure in thin film is technologically important. We show using a Ferrocene‐Naphthyridine hybrid molecule, the importance and selection of solvents in controlling possible assembly (phases) of molecules at solid‐air interface.