Phase transitions in Langmuir monolayers of polar molecules
Phase transitions in Langmuir monolayers of polar molecules
复制标题
极性分子朗缪尔单分子层中的相变
DOI：
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发表时间：
1987
期刊：
影响因子：
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通讯作者：
J. Joanny
中科院分区：
文献类型：
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作者：
D. Andelman;F. Brochard;J. Joanny
不溶性朗缪尔单分子膜的研究中存在的偶极力，可以有两个起源：永久偶极子在中性单分子膜和诱导偶极子在带电单分子膜。额外的长程排斥相互作用的主要作用是在热力学平衡下稳定波动相。相图可以在两种极限下得到：通过自由能的金斯堡-朗道展开（主要在平均场近似下）接近液-气临界点，以及在低温下通过自由能最小化。讨论了该理论在液-气、液膨胀-液冷凝和固-液相变实验中的可能应用。
Insoluble Langmuir monolayers are investigated in the presence of dipolar forces which can have two origins: permanent dipoles in neutral monolayers and induced dipoles in charged monolayers. The main effect of the additional long‐range repulsive interactions is to stabilize undulating phases at thermodynamic equilibrium. Phase diagrams are obtained in two limits: close to the liquid–gas critical point via a Ginzburg–Landau expansion of the free energy (mainly within a mean‐field approximation), and at low temperatures by free energy minimization. Possible applications of this theory to experiments at the liquid–gas, liquid expanded–liquid condensed, and solid–liquid transitions are discussed.