Intrachain distance mean square

Mean Square and Mean Reciprocal of Intrachain Distance... 

For an unperturbed (Gaussian) spring-bead chain the mean square and mean reciprocal rij ) of the distance rij between its beads i and j are equal to a i — j and 6/na Y i —These are well-known facts and are cited here without proof (see Ref. [2]). How are these averages expressed when the chain is perturbed by intrachain excluded-volume interactions This problem was first brought us by Peterlin [56] in 1955. Solution of it needs information about Wij(R), but, as mentioned above, work on this function is as yet in the process of development. 

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