Discrete solvation layering in confined binary liquids.
Discrete solvation layering in confined binary liquids.
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受限二元液体中的离散溶剂化分层。
DOI：
10.1021/la036200g
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
S. O’Shea
中科院分区：
文献类型：
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作者：
R. Lim;S. O’Shea
用原子力显微镜测量了Si3N4针尖与高取向热解石墨(HOPG)之间以及十六烷/OMCTS之间的角鲨烷/八甲基环四硅氧烷(OMCTS)混合物的溶剂化力分布。在HOPG上的测量揭示了在单力曲线上观察到角鲨烷和OMCTS的离散溶剂化层的振荡行为。第一溶剂化层(角鲨烷)对HOPG有很大的排斥力，表明它是强结合的。十六烷/OMCTS在云母上也观察到了振荡行为，但振荡出现在吸引区。在这种情况下，OMCTS层的有序度较低，周期稍大(约为1A)。这些结果与二元液体混合物的计算机模拟结果一致，但与表面力装置的实验结果定性地不同。
The solvation force profiles of squalane/octamethylcyclotetrasiloxane (OMCTS) mixtures confined between Si3N4 tips and highly oriented pyrolytic graphite (HOPG) and hexadecane/OMCTS confined between alkanethiol-functionalized tips and freshly cleaved mica have been measured by atomic force microscopy. Measurements on HOPG reveal oscillatory behavior where discrete solvation layers of both squalane and OMCTS are observed in a single force curve. The large repulsive force of the first solvation layer (squalane) on HOPG indicates that it is strongly bound. Oscillatory behavior is also observed for hexadecane/OMCTS on mica excepting that the oscillations are found in the attractive regime. The OMCTS layers in this case are less ordered with slightly larger (approximately 1 A) periodicities. These results are in agreement with computer simulations for binary liquid mixtures but differ qualitatively from surface force apparatus experiments.