Polymers Tend to Avoid Confined Spaces

Consider a chain molecule confined within a box of dimensions x = (v, and 

The same distribution function applies to y and z, because the dimensionalities are independent in the random-flight model. 

To get the full x-direction partition function qx, you must integrate the distribution over all possible beginnings and endings of the chain. 

Consider a simple case a chain confined between infinite plates, where x = is small but y, z Nb-. Then qv fv and qz (z- In this case, the full partition function is 

Now let s consider a polymer molecule adsorbed on a surface. Adsorption is a form of confinement. 

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