| Abstract
| - A set of covalently linked phenyl-amidophenyl-substituted porphyrin amphiphiles with n-C15H31 tailshave been synthesized and completely characterized. These amphiphiles form good Langmuir−Blodgett(LB) films at the air/water interface. Mean molecular areas for the series were measured from the isothermsand found to increase as the number of aliphatic chains increased from one to four. No influence of thesubphase pH was observed on the isotherms. LB films can be transferred successfully onto different solidsurfaces. The LB films were characterized using tapping mode atomic force microscopy (AFM). Bis-, tris-,and tetra-substituted porphyrins were found to be fairly good film-forming amphiphiles, whereas irregularaggregates were seen in the case of the monosubstituted porphyrin amphiphile. Multilayers were alsoformed with tetra-substituted amphiphiles on mica. Detailed AFM studies of tetra-substituted amphiphileshave been carried out to investigate the effect of preparation procedure and solid substrates on film formationand transfer. The absorption and fluorescence spectra for the amphiphiles in solution and LB films depositedonto mica and glass were recorded, which demonstrated the successful transfer of LB films onto thesubstrates and provided more information about the arrangement of porphyrin molecules within the LBfilms. For comparison, self-assembled monolayers (SAMs) and the cast thin films of the amphiphiles wereprepared and characterized.
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