Molecular Dynamics Studies of Glassy States: Supercooled Liquids and Amorphized Solids

在这个物理化学专业的理论与计算化学子项目中，Yip将研究液体和固体在玻璃化和非晶化的各个阶段的分子结构和动力学。将研究局部密度、动量、能量和应力的时间相关函数，并将其与热力学、结构、输运和粘弹性特性相结合，以提供物质玻璃态的统一分子描述。分子动力学和蒙特卡罗模拟将用于研究由一种和两种原子组成的液体和晶体的模型系统，这些模型系统在具有良好特征的热、应力或辐射环境下受到扰动。模拟结果将用于测试现有理论，阐明和关联不同类型的实验数据，并激发对过冷液体和非晶固体的新理论描述。特别令人感兴趣的是过冷中的一个温度区域，它明显高于传统的玻璃化转变点，并且明显发生动态交叉。

In this project in the Theoretical and Computational Chemistry Subprogram of the Physical Chemistry Program, Yip will investigate the molecular structure and dynamics of liquids and solids in various stages of vitrification and amorphization. Time correlation functions of local density, momentum, energy, and stress will be studied and combined with thermodynamic, structural, transport, and viscoelastic properties to provide a unified molecular description of glassy states of matter. Molecular dynamics and Monte Carlo simulations will be carried out to study model systems of liquids and crystals composed of one and two atomic species which have been perturbed under well-characterized thermal, stress, or irradiation environments. The simulation results will be used to test current theories, elucidate and correlate different types of experimental data, and motivate new theoretical descriptions of supercooled liquids and amorphized solids. Of particular interest is a temperature region in supercooling which is distinctly above the conventional glass transition point and where a dynamical crossover apparently occurs.