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works in this respect is that of Marrink and Tieleman (2001), which has suc-
cessfully modeled the exact structure of a Pn3m monoolein-inverted cubic
phase by considering both lipid and water molecules in an explicit manner.
Then, by imposing periodic boundary conditions, infi nitely large, bulk systems
could be predicted. Other contributions have followed on the atomistic simula-
tions and dynamics of lipid-based lyotropic liquid crystals (Horta et al., 2010;
Marrink and Tieleman, 2002), and it is to be expected that increasing compu-
tational speed will further trigger these types of simulation in the near future.
Clearly, this approach has the power to identify and locate each individual
molecule and to follow the dynamic of each of those at very short time scales
(nanoseconds). The main limitation, however, is that presently only the lyo-
tropic liquid crystal group spaces with the smallest lattice parameters such as
the columnar hexagonal or cubic Pn3m can be studied, and systems such as
the bicontinuous Ia3d cubic or the micellar Fd3m cubic still constitute a
challenge.
1.5
OUTLOOK AND CONCLUSIONS
Although self-assembly of lyotropic liquid crystals has been known since the
early 1960s, these systems are experiencing new interest today. Only in recent
years has the complexity of the thermodynamics and dynamics of self-assembly
in these intriguing systems been fully realized, which has catalyzed new studies
and developments. Recent progress in the fi eld has been carried out in all
directions: New applications have fl ourished, new methods have been devel-
oped and assessed in order to shed light on the structure of these systems, and
when experiments have proved challenging to be carried out, simulations have
fi lled some of the gaps left opened. Last, but not least, new theoretical
approaches have been put in place that have elucidated some of the unex-
plained features of these unique systems. It is to be hoped and expected that
this continuous learning progress will continue and increase our understanding
of these systems, remarkable for their compositional simplicity, but challenging
from the point view of self-assembly complexity.
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