Self-assembled+monolayer


 * __Self assembled monolayers__**

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A **self assembled monolayer** (**SAM**) is an organized layer of amphiphilic molecules in which one end of the molecule, the “head group” shows a special affinity for a substrate. SAMs also consist of a tail with a functional group at the terminal end as seen in the above image. SAMs are created by the chemisorption of hydrophilic “head groups” onto a substrate from either the vapor or liquid phase followed by a slow two-dimensional organization of hydrophobic “tail groups”. Initially, adsorbate molecules form either a disordered mass of molecules or form a “lying down phase”, and over a period of hours, begin to form crystalline or semicrystalline structures on the substrate surface. The hydrophilic “head groups” assemble together on the substrate, while the hydrophobic tail groups assemble far from the substrate. Areas of close-packed molecules nucleate and grow until the surface of the substrate is covered in a single monolayer.

Two self-assembled monolayers I will be looking at in the future of my project.

__Octanethiol on gold (Au)__

[|http://images.google.com/imgres?imgurl=http://chemistry.nd.edu/images/faculty_galleries/2%2520-%2520BT%2520(2).jpg&imgrefurl=http://chemistry.nd.edu/faculty/detail/skandel/photos/1149/&usg=__u0ZxfTtOkv0cs7v0ZeGrjw9wfyU=&h=344&w=325&sz=82&hl=en&start=13&um=1&tbnid=7NkvlhbdyjEeoM:&tbnh=120&tbnw=113&prev=/images%3Fq%3Doctanethiol%2Bimage%26hl%3Den%26sa%3DN%26um%3D1]

__Fullerenes (C70 and C60) on gold- Buckyball__ A fullerene is any molecule composed entirely of carbon, in the form of a hollow sphere, ellipsoid, or tube. C70 is called this because it is made up of 70 Carbon atoms, whereas C60 is made up of 60 carbon atoms.

[|http://images.google.com/imgres?imgurl=http://chemistry.nd.edu/images/faculty_galleries/2%2520-%2520BT%2520(2).jpg&imgrefurl=http://chemistry.nd.edu/faculty/detail/skandel/photos/1149/&usg=__u0ZxfTtOkv0cs7v0ZeGrjw9wfyU=&h=344&w=325&sz=82&hl=en&start=13&um=1&tbnid=7NkvlhbdyjEeoM:&tbnh=120&tbnw=113&prev=/images%3Fq%3Doctanethiol%2Bimage%26hl%3Den%26sa%3DN%26um%3D1]

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