摘要： Rigorously speaking, entropy is slightly non-extensive, and this non-extensiveness, which characterizes the degree of fluctuations, can contribute to effective interactions between mesoscopic objects. In this paper, we consider a pair of macroions, each accompanied by 1000 counterions, and with a cell-model description we demonstrate that the slow variation of non-extensiveness in counterion entropy over macroionic distance leads to an effective long-range attraction between the macroions. With the aid of Monte Carlo simulation and a Bragg-Williams theory including counterion number fluctuations, we find the depth of attraction in free energy to be approximately 0.2 k B T . The observation in our cell-model study provides an insight for further understanding of effective interactions in real macroionic systems. Couterion number fluctuations over the cells lead to an effective like-charge attraction between macroions. 其他題名： Phys Chem Chem Phys 出版者： England 出版日期： 2014-01-07 出處： Physical chemistry chemical physics : PCCP, 2014-01, Vol.16 (1), p.297-33 資源來源： Royal Society of Chemistry 識別號： ISSN: 1463-9076 識別號： ISSN: 1463-9084 識別號： EISSN: 1463-9084 識別號： DOI: 10.1039/c3cp53318b 識別號： PMID: 24253489
