Structural Characterization of Monolayers

Porter M D, Bright T B, Allara D L and Chidsey C E D 1987 Spontaneously organized molecular assemblies. 4. Structural characterization of normal-alkyl thiol monolayers on gold by optical ellipsometry, infrared-spectroscopy, and electrochemistry J. Am. Chem. Soc. 109 3559-68... 

Nuzzo R G, Dubois L FI and Allara D L 1990 Fundamental-studies of microscopic wetting on organic-surfaces. 1. formation and structural characterization of a self-consistent series of polyfunctional organic monolayers J. Am. Chem. Soc. 112 558-69... 

Description of the different mimetic systems will be the starting point of the presentation (Sect. 2). Preparation and characterization of monolayers (Langmuir films), Langmuir-Blodgett (LB) films, self-assembled (SA) mono-layers and multilayers, aqueous micelles, reversed micelles, microemulsions, surfactant vesicles, polymerized vesicles, polymeric vesicles, tubules, rods and related SA structures, bilayer lipid membranes (BLMs), cast multibilayers, polymers, polymeric membranes, and other systems will be delineated in sufficient detail to enable the neophyte to utilize these systems. Ample references will be provided to primary and secondary sources. 

The purpose of this chapter is to review recent progress in surface structural characterization of select oxide films, with particular emphasis on systems that are sensitive to some of the problems listed above. By thin , we mean a few monolayers up to -1000 A. We take the approach of addressing the issues of oxidation chemistry, either during or after film formation, and lattice and symmetry mismatch with the substrate. We examine representative case studies that illustrate the materials issues listed above. It is assumed that the reader is... 

A. Tadjeddine, D. Guay, M. Ladouceur, G. Tourillon, Electronic and structural characterization of underpotentially deposited submonolayers and monolayer of copper on gold (111) studied by in situ X-ray-absorption spectroscopy. Phys. Rev. Lett. 66, 2235-2238, 1991. 

Booking T., James M., Coster H. G. L., Chilcott T. C. and Barrow K. D. (2004), Structural characterization of organic multilayers on silicon(lll) formed by immobilization of molecular films on functionalized Si-C linked monolayers , Langmuir 20, 9227-9235. 

Nakano. T.. Yamada. Y., Matsuo, T., Yamada, S. In-situ second-harmonic generation and luminescence measurements for structural characterization of ruthenium-polypyridine complex monolayers with two and four aliphatic tails at the air/water interface. J. Phys. Chem. B 102, 8569-8573 (1998)... 

Fritz, S. E. et ah. Structural characterization of a pentacene monolayer on an amorphous Si02 substrate with grazing incidence x-ray diffraction, J. Am. Chem. Soc., 126, 4084, 2004. 

Fritz, S.E. et al.. Structural characterization of a pentacene monolayer on an amorphous... 

Films or membranes of silkworm silk have been produced by air-drying aqueous solutions prepared from the concentrated salts, followed by dialysis (11,28). The films, which are water soluble, generally contain silk in the silk I conformation with a significant content of random coil. Many different treatments have been used to modify these films to decrease their water solubility by converting silk I to silk II in a process found useful for enzyme entrapment (28). Silk membranes have also been cast from fibroin solutions and characterized for permeation properties. Oxygen and water vapor transmission rates were dependent on the exposure conditions to methanol to facilitate the conversion to silk II (29). Thin monolayer films have been formed from solubilized silkworm silk using Langmuir techniques to facilitate structural characterization of the protein (30). Resolubilized silkworm cocoon silk has been spun into fibers (31), as have recombinant silkworm silks (32). 

The TER-XSW method opens the possibility of using XSW to profile nanoscale metal structures and ion distributions above solid surfaces and at fluid-solid interfaces. Applications of TER-XSW have included direct observation of the diffuse electrical double layer at the charged membrane and electrolyte interfaces (Bedzyk et al. 1990 Wang et al. 2001), structural characterization of self-assembled organic monolayers (Lin et al. 1997), and determining metal ion partitioning at oxide-biofilm interfaces (Templeton et al. 2001). These applications are discussed later in this chapter. 

R. G. Nuzzo, L. H. Dubois and D. L Allara, Tundamental Studies of Microscopic Wetting on Organic Surfaces. I. Formation and Structural Characterization of a Self-Consistent Series of Polyfunctional Organic Monolayers, J. Am. Chem. Soc.. 112. 558-569 (1990). 

This paper covers the deposition and characterization of monolayers of dodecyl phosphate, 12-hydroxy-dodecyl phosphate, and a mixture of the two from aqueous solutions of their ammonium salts onto three different substrates titanium oxide and titanium metal films, deposited by physical vapor deposition onto glass and silicon substrates (serving as smooth, flat model surfaces), and a special titanium dental implant surface with a rough, highly corrugated surface. The aim of the present investigation is twofold first, to describe the physicochemical and structural properties of the single-component and mixed SAMs on titanium (oxide), and second, to test the... 

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