AQUEOUS ION TRANSPORT PROPERTIES AND WATER REORIENTATION DYNAMICS FROM AMBIENT TO SUPERCRITICAL CONDITIONS
AQUEOUS ION TRANSPORT PROPERTIES AND WATER REORIENTATION DYNAMICS FROM AMBIENT TO SUPERCRITICAL CONDITIONS
复制标题
从环境到超临界条件的水离子传输特性和水重新定向动力学
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
J. Hyun
中科院分区：
文献类型：
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作者：
P. Balbuena;K. Johnston;P. Rossky;J. Hyun
离子输运性质，包括摩擦系数，瓦尔登产品（产品的电导率和粘度），和极限等效电导预测在水中在高温下使用连续介质模型。分子动力学计算机模拟是用来确定水的旋转重定向时间在第一协调壳相比，散装，并将结果纳入流体动力学表达式的离子摩擦系数。沿着水的共存曲线，该模型所隐含的有效斯托克斯-爱因斯坦半径相对恒定。然而，对于Cl-，K+和Rb+，该半径在典型的超临界水条件下增加，其中第一壳层水分子的运动与离子的运动更紧密地耦合。对于Na+，在较高的溶剂密度下，耦合已经相当强。增量的摩擦系数超过裸离子斯托克斯-爱因斯坦的结果贡献了更大的一部分总超临界...
Ion transport properties including the friction coefficient, Walden product (product of conductivity and viscosity), and the limiting equivalent conductance are predicted in water at elevated temperatures using a semicontinuum model. Molecular dynamics computer simulation is used to determine water rotational reorientation times in the first coordination shell compared with the bulk, and the results are incorporated into a hydrodynamic expression for the ionic friction coefficient. Along the coexistence curve of water, the effective Stokes−Einstein radius implied by the model is relatively constant. However, for Cl-, K+, and Rb+, this radius increases at typical supercritical water conditions, where the motion of the first shell water molecules is coupled more closely to that of the ion. For Na+, the coupling is already quite strong at higher solvent densities. The increment to the friction coefficient in excess of the bare ion Stokes−Einstein result contributes a larger fraction of the total in supercrit...