Departamento de Fı́sica Atómica, Molecular y Nuclear, Área de Fı́sica Teórica, Universidad de Sevilla , Avenida de Reina Mercedes s/n, 41012 Sevilla, Spain.
Langmuir. 2017 Oct 24;33(42):11779-11787. doi: 10.1021/acs.langmuir.7b02347. Epub 2017 Sep 22.
We study the morphologies of nematic nanodrops in a vapor of a discotic nematogen by Monte Carlo simulations. The fluid interactions are modeled by a Gay-Berne model with molecular elongations of κ = 0.3 and 0.5 and different values of the energy anisotropy parameter κ' in the range of temperature T in which the nematic coexists with a vapor phase. We considered nanodrops of N = 4000 and 32 000 particles. For κ > κ', we observe that nanodrops are quite spherical (even for N = 4000 nanodrops), with a homogeneous director field for κ = 0.3 and a bipolar nematic configuration with tangential anchoring for κ = 0.5. By increasing the value of κ', nanodrops change from spherical to lens-shaped for κ = 0.3, and for κ = 0.5, spherical nanodrops with homeotropic anchoring and a disclination ring located on its equatorial plane are observed. Although no radial nanodrops are observed, isotropic liquid nanodrops with a paranematic shell and radial texture are observed for temperatures slightly above the vapor-isotropic-nematic triple point when the vapor-isotropic interface is completely wet by the nematic phase.
我们通过蒙特卡罗模拟研究了碟状向列相织构蒸气中向列型纳米液滴的形态。采用 Gay-Berne 模型模拟流体相互作用，κ 值分别为 0.3 和 0.5，温度范围为 T，其中向列相与蒸气相共存，各向异性参数 κ' 的值不同。我们考虑了 N = 4000 和 32000 个粒子的纳米液滴。对于 κ > κ'，我们观察到纳米液滴相当球形（即使对于 N = 4000 个纳米液滴），对于 κ = 0.3，具有各向同性的director 场，对于 κ = 0.5，具有具有切向锚定的双极向列型配置。随着 κ' 值的增加，对于 κ = 0.3，纳米液滴从球形变为透镜形，对于 κ = 0.5，观察到具有垂直锚定的球形纳米液滴和位于赤道平面上的一个位错环。尽管没有观察到径向纳米液滴，但当蒸气各向同性界面完全被向列相润湿时，在略高于蒸气各向同性-向列三相点的温度下，观察到具有向列型外壳和径向织构的各向同性液体纳米液滴。
