spheres, and the change in free energy upon dimerization is written out, labeled here
pmonomeτ→dτmeτ_ ʌ scconj step consists of forming bonds between dimers to obtain
chains; the change in free energy due to chain formation from dimers, labeled as
p^dιmer→chaιn, ∣g a∣so (jerjvec[ usj∏g TPTl. The total contribution to the free energy
due to chain connectivity is thus the sum of the two contributions ∖monamer^dmer and
^dιmer→chaιn' ∖γ]ιen this path towards chain formation is taken, any segment on a
given chain is “aware” of the presence of its two nearest neighbors and of the presence
of the segments next to them, as opposed to the chain term in the original SAFT-HS.
This implies that more detailed information about the chain formation is incorpo-
rated into the chain EOS, thus improving the predictive abilities of the equation of
state. The new chain free energy contribution has the following form [80]
—— = J2χimiyΓhT ~ ΣXi (~T ~ ɪ) ln^⅛i) - Σ ∙τ≈T ln⅛)' (2.17)
1V J∖ J. 1∖ a Iv JL ∖ Δ ' Z
iι ι
where g^(σn) is the site-site correlation function at contact for a mixture of hard
dispheres. The form of the site-site correlation function proposed by Ghonasgi and
Chapman [80, 84] is used in this work.
hd( ʌ _ ɪ + K2σiσj∕σij + cζf17(σiσ√σij)617
(2.18)
9ij l гз) 2(1 - ζ3)2
where, c=26.4503.
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