Behavior of a wetting phase near a solid boundary: vapor near a weakly attractive surface
Behavior of a wetting phase near a solid boundary: vapor near a weakly attractive surface
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固体边界附近润湿相的行为：弱吸引力表面附近的蒸气
DOI：
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发表时间：
2006
期刊：
影响因子：
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通讯作者：
A. Geiger
中科院分区：
文献类型：
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作者：
A. Oleinikova;I. Brovchenko;A. Geiger
抽象的。
长程引力弱表面附近LJ蒸汽的密度分布
沿着孔隙共存曲线研究了流体壁电位。有两个局部密度最大值附近的孔壁：第一个是由本地化的分子在流体壁电位的最小值，和第二个反映了吸附的分子在第一层在较高的密度。此外，第三，弱密度最大值观察到接近临界温度由于流体壁势的长程吸引尾和丢失邻居的效果之间的竞争。该最大值将由于缺少相邻效应而导致的朝向表面的逐渐密度耗尽的区域和远离表面的吸附区域分开，在吸附区域中，由于吸引性流体壁势而朝向表面的密度逐渐增加。当接近体临界温度时，由于体相关长度的发散，该最大值远离表面。各种方程来描述蒸汽密度分布的适用性进行了检查。在低温下蒸气的过量吸附在较高温度下转变为过量消耗。交叉温度随着孔径的增大和流体-壁面相互作用的加强而升高。讨论了表面场不为零的伊辛模型的表面临界性态理论及其在流体上的映射问题。
Abstract.
Density profiles of a LJ vapor near a weakly attractive surface with long-range
fluid wall potential was studied along the pore coexistence curve. There are two localized density maxima near the pore wall: the first one is caused by localization of the molecules in the minimum of the fluid-wall potential, and the second one reflects adsorption of molecules at the first layer at higher densities. In addition, a third, weak density maximum is observed close to the critical temperature due to the competition between the long-range attractive tail of the fluid-wall potential and the effect of missing neighbors. This maximum separates the region of a gradual density depletion toward the surface due to the missing neighbor effect and the adsorption region further from the surface, where the density gradually increases toward the surface due to the attractive fluid-wall potential. When approaching the bulk critical temperature, this maximum moves away from the surface due to the divergence of the bulk correlation length. Applicability of various equations to describe the vapor density profiles is examined. Excess adsorption of vapor at low temperatures turns into excess depletion at higher temperatures. The crossover temperature increases with increasing pore size and strengthening fluid-wall interaction. The problems of the theory of the surface critical behavior of Ising models in a case of a non vanishing surface field and its mapping on a fluid is discussed.