or
dβV{xt's∖z) _ 1 dexp{-βVγxt'sl{z]) _ δ∖z)
dz exp(-∕JV1earf,sl(z)) dz δ(z) ,
and for the other segments,
exp(-βVext,sl (z)) = H{z - Ц), (6.40)
j δ
where H(z) is the Heaviside step function. Or,
= 1 dexp(-^sl(^)) = φ-⅜)
dz exp(-βVjext'sl(zY dz H(z-⅛β' ^
For all the segments of the chains grafted to the surface at z = H and the free
polymer, the external potential due to the surface at z = 0 is
expH^1W) = H(,z-¾ (6.42)
j 2
and eq. 6.41 applies.
Hence,
1 δβtt
A~δH
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