Theory of the Nematic-Isotropic Transition in a Restricted Geometry
Theory of the Nematic-Isotropic Transition in a Restricted Geometry
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DOI：
10.1080/02678298708086677
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发表时间：
1987-05
期刊：
影响因子：
2.2
通讯作者：
A. Poniewierski;T. J. Sluckint
中科院分区：
文献类型：
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作者：
A. Poniewierski;T. J. Sluckint
摘要我们讨论，使用Landaude Gennes形式主义，向列型各向同性的转变温度为放置在两个平行板之间的系统，在每个板相同的垂面或均匀的边界条件。根据边界条件的性质，相变处的温度可以随着逆样品厚度D-1的增加而增加或减少。在所有的情况下，过渡终止于足够大的D-1的临界点，超过该临界点，双相和各向同性相不再明显。的相变温度是很好地描述了一个液晶类似的开尔文方程，可以推广到一个精确的克劳修斯-克拉珀龙关系。在许多情况下，从热力学的角度来看，系统的行为就好像它处于一个整体有序场中。有限的几何形状限制了非均匀或各向同性润湿膜的生长。我们讨论了Horn、Israelachvili和Perez的分离压实验[15]。芬...
Abstract We discuss, using a Landaude Gennes formalism, the nematic-isotropic transition temperature for a system placed between two parallel plates, subject to identical homeotropic or homogeneous boundary conditions at each plate. The temperature at the phase transition may increase or decrease as the inverse sample thickness, D-1, increases, depending on the nature of the boundary conditions. In all cases the transition terminates at a critical point for sufficiently large D-1, beyond which the nematic and isotropic phases are no longer distinct. The phase transition temperature is well described by a liquid crystal analogy of the Kelvin equation which can be generalized to give an exact Clausius-Clapeyron relation. Under many circumstances the system behaves from a thermodynamic point of view as though it were in a bulk ordering field. The finite geometry restricts the growth of nematic or isotropic wetting films. We discuss the disjoining pressure experiment of Horn, Israelachvili and Perez [15]. Fin...