
296 Perturbation Theories for Fluids and Solids
developed for particular nonadditive hard sphere (NAHS) mixtures, some of which
will be discussed in Section 10.3. A generalization of the Rosenfeld FMT for the
general case of NAHS mixtures with moderate nonadditivity has been developed by
Schmidt (2004). The excess free energy functional is written as
βF
E
[
ρ
1
(
r
)
, ρ
2
(
r
)
]
=
3
i,j=0
K
(
12
)
ij
r −r
ij
n
(
1
)
l
(
r
)
,
n
(
2
)
l
r
drdr
,
(9.67)
where l = 0, 1, 2, 3, K
(12)
ij
(r) is a function controlling the range on nonlocality between
unlike species, and
n
(
k
)
l
(
r
)
=
ρ
k
(
r
)
w
(
k
)
l
r −r
dr
, k = 1, 2, (9.68)
with the Kierlik and Rosinberg (1990) scalar form adopted ...