is used here, where
МЕХЛв[{Ра}] = У *Φ[nθ(r)]∙
(4.5)
Φ[nct(r)] is given by
ɪ г 1 ι∕ι ∖ ∣ ^,1^2 ^,2 Tlυl∙Tlv2 7⅛(τ⅛2∙^⅛2) z. c∖
ФЫ = -no ɪn(l - n3) + — + 24πtl _ Пз)2 - - 8я(1_„з)г. (4.6)
and na are the weighted densities. The long range attraction is included using the
mean field approximation.
-∣ Ilb Ilb n
Aex^t[{pa}] = ^Yι ⅛*2<≈(∣r2-rl∣)p∞<(r1)p∞>(r2). (4.7)
a=l 7=1 ∙'∣Γ2-Γ1∣>σα.y
Aex,assoc can ɪɔθ writtθn following TPTl using the extension (to fluid mixtures
with molecules having multiple bonding sites) and general notation of Chapman [58,
62] as,
Mfx'ωηW] = ∕⅛ιf>s<*(rι) £ ɑnjɑ(n) -
j α=l A∈Γ<q) '
(4.8)
The first summation is over all the segments α, and the second over all the association
sites on segment a where f(ɑɔ is the set of all the associating sites on segment а. Хд
denotes the fraction of segments of type a which are not bonded at their site A. This
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