Measuring the equation of state of a hard-disc fluid

Abstract

We use video microscopy to study a two-dimensional (2D) model fluid of charged colloidal particles suspended in water and compute the pressure from the measured particle configurations. Direct experimental control over the particle density by means of optical tweezers allows the precise measurement of pressure as a function of density. We compare our data with theoretical predictions for the equation of state, the pair-correlation function and the compressibility of a hard-disc fluid and find good agreement, both for the fluid and the solid phase. In particular the location of the transition point agrees well with results from Monte Carlo simulations.

arXiv comment7 pages, to appear in EPL, slightly corrected version

References in corpus (3)

• Computer simulations of the two-dimensional melting transition using hard disks
• Elastic moduli, dislocation core energy and melting of hard disks in two dimensions
• Orientational order of the two-dimensional hard disk system

Cited by in corpus (7)

• Colloidal Hard Spheres: Triumphs, Challenges and Mysteries
• Inhomogeneous hard-sphere mixtures: Manifestations of structural crossover
• The law of action and reaction for the effective force in a nonequilibrium colloidal system
• Molecular dynamics and theory for the contact values of the radial distribution functions of hard-disk fluid mixtures
• Structural characterisation of polycrystalline colloidal monolayers in the presence of aspherical impurities
• The rheology of confined colloidal hard discs
• Theoretical calculation of the phase behavior of colloidal membranes