Abstract
We have applied the DFT formalism to the study of the orientational freezing of HCB and proved that through the ELA the most relevant theories proposed in the literature are recovered. This framework thus provides a connection between them and makes clear the assumptions under which they are obtained. The latter fact makes easier to improve them. When the formalism is applied in D > 2 the results are very satisfactory when compared to the simulations (in particular, the theory is exact in the limit D → ∞). The I-N transition predicted is first order in this case. However the results for D = 2 are not so good: the I-N predicted is always continuous while the simulations show a change in the order of the transition. Its location is also too deviated from that obtained from simulations. Nevertheless the results for the equation of state are reasonably accurate, specially for low aspect ratios. We conclude that the simple factorisation arising from the approximation used for the DCF is not enough to account for such a complex behaviour. The possibility of a coupling with translational degrees of freedom is not ruled out as an explanation for the change of order of the transition, because this change happens when this transition is very close to the fluid-solid transition. Anyway an improvement of the isotropic DCF seems to be neccessary to get more accurate results.
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© 1993 Springer-Verlag
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Cuesta, J.A. (1993). Orientational freezing within the effective liquid approach. In: Garrido, L. (eds) Complex Fluids. Lecture Notes in Physics, vol 415. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3540563962_73
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DOI: https://doi.org/10.1007/3540563962_73
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