Van der Waals-Zeeman Institute, University of Amsterdam, Amsterdam, The Netherlands.
J Chem Phys. 2013 Sep 7;139(9):094903. doi: 10.1063/1.4819896.
We report Monte Carlo simulations of phase behavior of colloidal suspensions with near-critical binary solvents using effective pair potentials from experiments. At off-critical solvent composition, the calculated phase diagram agrees well with measurements of the experimental system, indicating that many-body effects are limited. Close to the critical composition, however, agreement between experiment and simulation becomes poorer, signaling the increased importance of many-body effects. Both at and off the critical solvent concentration, the colloidal phase diagram is qualitatively similar to those of molecular systems and obeys the principle of corresponding states with one striking difference: it occurs in a narrow temperature interval of <1 °C below the solvent phase separation temperature.
我们使用实验得到的有效对势，对具有近临界二元溶剂的胶体悬浮液的相行为进行了蒙特卡罗模拟。在远离临界溶剂组成的情况下，计算得到的相图与实验体系的测量结果吻合良好，表明多体效应对体系的影响有限。然而，在接近临界溶剂组成的情况下，实验和模拟之间的一致性变差，这表明多体效应对体系的影响变得更加重要。无论是在临界溶剂浓度还是在其附近，胶体相图在定性上与分子体系相似，并遵循对应态原理，但有一个显著的区别：它发生在低于溶剂分相温度的<1°C的狭窄温度间隔内。
