The nature of limits to deposition density

The quantity pt reflects this maximum density of surface sites. Its value was determined by the above experiments to be in the range of Pt = 1.9 to 2.5 pm/pm. Given the small area occupied by a DNA-SWCNT (2 nm x 2 pm = 0.004 pm, or just 0.4% of the surface occupied), what could be the nature of the sites to give such a small surface density Here we consider both the traditional RSA theory and a new formulation to answer this question. 

Let us first consider the possibility that these surface sites are a result of electrostatic exclusion by the deposited nanotubes. As a conservative estimate, suppose that each nanotube excludes an 

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