Pair structure of the hard-sphere Yukawa fluid

F. WESTERMEIER; HOLMQVIST, P.; ADOLFO J. BANCHIO; G. NÄGELE; HEINEN, M.

Kiel

Workshop; DIAGNOSTICS AND SIMULATION OF DUSTY PLASMAS; 2012

We present a comprehensive survey of static pair-structure functions for fluids of Yukawalike spherical particles. The performance of various integral equation schemes for the structure factor S(q) and the radial distribution function g(r) is assessed in comparison with computer simulations [1] and static light scattering and small-angle X-ray scattering experiments on charged colloidal particles [1, 2]. We demonstrate that the novel, analytic modified penetratingbackground corrected rescaled mean spherical approximation (MPB-RMSA) [1] scheme predicts S(q) and g(r) in excellent agreement with simulations and the computationally demanding, non-analytically solvable Rogers-Young scheme. By virtue of its combined high accuracy and quick analytic solution, the MPB-RMSA is the only method allowing for accurate real-time fitting of experimental scattering data. In addition, the MPB-RMSA allows high-resolution parameter studies of the liquid-crystal phase boundary of Yukawa-fluids [1] and of scaling relations for the pair-structure functions, in particular regarding the nearest-neighbor cage size of highly coupled particles at low screening [1, 2]. By construction, the MPB-RMSA is specially adept to the high coupling regime common to dilute suspensions of charged colloids at low salinity, and dusty plasmas with effectively point-like dust particles. References[1] F. Westermeier, B. Fischer, W. Roseker, G. Grübel, G. Nägele, and M. Heinen, submitted.[2] M. Heinen, P. Holmqvist, A. J. Banchio, and G. Nägele, J. Chem. Phys. 134, 044532 and129901 (2011).