A numerical method for the study of nucleation of ordered phases

作者：Lin Ling; Cheng Xiuyuan; E Weinan; Shi An Chang; Zhang Pingwen^*

来源：Journal of Computational Physics, 2010, 229(5): 1797-1809.

DOI：10.1016/j.jcp.2009.11.009

• Nucleation
• Ordered phase
• Critical nuclei
• Minimum energy path (MEP)
• String method
• Liquid crystal
• Block copolymer

A numerical approach based on the string method is developed to study nucleation of ordered phases in first-order phase transitions. Among other things, this method allows an efficient computation of the minimum energy path (MEP) during the nucleation process. The MEP provides information about the size, shape and free energy barrier of the critical nucleus. To improve the efficiency of the string method, a special initialization process is proposed. Constraints from physical models are treated using two methods, a generalized coordinates method and a projection method. Strategies for choosing the computational domain and defining the nucleus boundary are also introduced. The validity of our approach is illustrated by two nontrivial examples from soft condensed matter physics, namely the nematic-isotropic transition of liquid crystals and the ordered-to-ordered phase transition of diblock copolymers.

• 出版日期2010-3-1
• 单位北京大学