Recent simulation studies have drawn attention to the shoulder which forms inthe second peak of the radial distribution function of hard-spheres atdensities close to freezing and which is associated with local crystallineordering in the dense fluid. We address this structural precursor to freezingusing an inhomogeneous integral equation theory capable of describing localpacking constraints to a high level of accuracy. The addition of a short-rangeattractive interaction leads to a well known broadening of the fluid-solidcoexistence region as a function of attraction strength. The appearence of ashoulder in our calculated radial distribution functions is found to beconsistent with the broadened coexistence region for a simple model potential,thus demonstrating that the shoulder is not exclusively a high density packingeffect.
展开▼
