ular simulations of these systems are computationally expensive and are limited to
short chain molecules with simple interactions. Furthermore, DFTs can take advan-
tage of the symmetry of the system, to further reduce the computational time. For
example, studying the (parallel∕perpendicular) lamellar morphologies of symmetric
diblock copolymers using DFT∕SCF theories is an one dimensional problem or mixed
morphologies is a two-dimensional problem. Thus, DFTs provide an approach that
incorporates molecular-level detail but is simple enough that the calculation time is
modest and physical insight is retained even in complex situations. A thorough review
of classical DFT is given by Evans [56] and recently by Wu and Li [145].
Frischknecht et. al. [50] were the first to study symmetric diblock copolymers
confined between two parallel smooth surfaces in detail with DFT. They applied
Chandler-McCoy-Singer (CMS) DFT to investigate the lamellar morphologies of di-
block copolymers with different incompatibilities between their blocks and at different
surface interaction strengths. However, the applicability of CMS-DFT, which is based
on the polymer reference interaction site model (PRISM) theory [105] for the bulk
polymer fluids, is complicated by the ambiguities regarding the closure relations to be
used for specific applications. Cao and Wu [112, 146] have also applied their DFT [61]
to study the microstructure of block copolymers near planar surfaces and in slit-like
pores. Ye et. al. [147] also applied their DFT [148, 149] to study the adsorption of
block copolymers at selective walls. Like the DFT by Cao and Wu, their theory also
applies the weighted density functional approximation to the bulk equation of state
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