Fundamental-Measure Density Functional for Mixtures of Parallel Hard Cylinders Articles uri icon

publication date

  • May 2008

start page

  • 51205

issue

  • 5

volume

  • 77

international standard serial number (ISSN)

  • 1539-3755

electronic international standard serial number (EISSN)

  • 1550-2376

abstract

  • We obtain a fundamental-measure density functional for mixtures of parallel hard cylinders. For this purpose we first generalize to multicomponent mixtures the fundamental-measure functional proposed by Tarazona and Rosenfeld for a one-component hard disk fluid, through a method alternative to the cavity formalism of those authors. We show the equivalence of both methods when applied to two-dimensional fluids. The density functional so obtained reduces to the exact density functional for one-dimensional mixtures of hard rods when applied to one-dimensional profiles. In a second step, we apply an idea put forward some time ago by two of us, based again on a dimensional reduction of the system, and derive a density functional for mixtures of parallel hard cylinders. We explore some features of this functional by determining the fluid-fluid demixing spinodals for a binary mixture of cylinders with the same volume, and by calculating the direct correlation functions.