The name is absent

Helmholtz free energy functional (Λ[{p_α}]) as

^^[{O^] = ^-K^eat(r) Vtt = l,m,              (5.8)

where μ_a is chemical potential of the segment a, and V^^xt is the external field acting
onto it. Solution of the set of these (Euler-Lagrange) equations gives the equilibrium
density profile of the segments. To derive the Helmholtz free energy, the copolymer
chain molecule is considered as the limit of complete association of a mixture of
associating atomic molecules (or associating segments), with off-centered association
sites. The Helmholtz free energy functional of such a mixture of associating segments
can be written as

A[{p_α}] =          + A^EX,hs [{p_α}] + A^EX,chain[{p_a}] + A^EX,att[{p_a}], (5.9)

where A^ld is the ideal free energy of the segments, A^EX,hs is the excess free energy
due to the excluded volume of the segments (hard sphere repulsions), A^EX'^cham is
the excess free energy due to chain formation in the limit of complete association of
the segments, and A^ex,m is the excess free energy due to the long range attractions
between the segments.

The individual free energies and their functional derivatives were derived in chap-
ter 4. Here, the final equilibrium density profile of the segments and grand free energy

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