Piñero J, Bhuiyan L B, Rescic J, Vlachy V
Laboratory of Theoretical Physics, Department of Physics, University of Puerto Rico, San Juan, Puerto Rico.
J Chem Phys. 2008 Jun 7;128(21):214904. doi: 10.1063/1.2919134.
The structural properties of linear polyelectrolyte solutions in the presence of a salt as evidenced through ionic correlations in the inhomogeneous atmosphere around a polyion and their consequence such as the catalytic potential are studied by using Monte Carlo simulation techniques. The simulations are performed on the cylindrical cell model where a uniformly charged hard cylinder mimics the linear polyion, which is caged in its own cylindrical cell containing counterions and salt. The cell (volume) average of the interionic correlations is presented as a function of the polyion and salt concentrations and ion radius. These results are utilized to study the catalytic effects of polyions as manifested through the changes in the collision frequency between ions in the double layer surrounding the polyion relative to that in the pure electrolyte solution. The reported results suggest a strong influence of the added salt/polyelectrolyte concentration ratio on the structural properties of the solution and hence on ion-ion collision frequency. The machine simulations are supplemented by nonlinear Poisson-Boltzmann results. Fair agreement between two different theoretical methods of calculating the collision frequency is obtained.
通过聚离子周围非均匀气氛中的离子相关性及其催化潜力等结果来证明，采用蒙特卡罗模拟技术研究了存在盐时线性聚电解质溶液的结构性质。模拟是在圆柱形电池模型上进行的，其中均匀带电的硬圆柱体模拟线性聚离子，该聚离子被关在其自身包含抗衡离子和盐的圆柱形电池中。离子间相关性的电池（体积）平均值作为聚离子、盐浓度和离子半径的函数给出。这些结果被用于研究聚离子的催化作用，其表现为聚离子周围双层中离子间碰撞频率相对于纯电解质溶液中碰撞频率的变化。所报道的结果表明，添加的盐/聚电解质浓度比对溶液的结构性质有很大影响，进而对离子-离子碰撞频率有很大影响。机器模拟由非线性泊松-玻尔兹曼结果补充。两种不同计算碰撞频率的理论方法之间获得了合理的一致性。
