Thermodynamics, Structure and Dynamics of Crystal-melt Interfaces

堪萨斯大学的Brian Laird教授得到了理论和计算化学计划的支持，负责研究晶体-熔体界面的热力学、结构和动力学。这项工作是通过对晶体从液态生长的计算和理论建模以及这些方法的进一步发展来完成的。特别强调的是确定液体的结构、分子相互作用的细节以及第二组分的存在如何影响界面的各向异性。此外，还应用于结构、动力学和界面自由能体系的计算，如丁二腈或甲戊酸，以确定这些方法对非常复杂的体系的适用性。这项工作是通过发展和应用计算机模拟方法进行的，如蒙特卡罗，并使用经典的密度泛函理论。熔体中晶体的成核和生长影响着许多日常发生和活动。这些包括冶金中的铜焊、铸造和焊接、医疗器官的低温保存、大气事件造成的天气条件，以及用于结构表征的蛋白质结晶。在这项工作中，计算机算法和基本理论被提出并应用于了解潜在的相互作用、结构偏差和其他分子的存在如何影响晶体从液体中生长。学习如何控制结晶将对上述所有领域产生积极的影响。

Professor Brian Laird, of the University of Kansas, is supported by the Theoretical and Computational Chemistry Program to perform research on the thermodynamics, structure and dynamics of crystal-melt interfaces. This work is accomplished by both computational and theoretical modeling of growth of crystals from the liquid state and by further development of these methods. Particular emphasis is on determining how the structure of the liquid, details of the molecular interactions, and presence of a second component influence the anisotropy of the interface. In addition applications to the calculation of structure, dynamics and interfacial free energies systems such as succinonitrile or pivalic acid are performed to determine the applicability of such methods to very complex systems. The work is performed by development and application of computer simulation methods, such as Monte Carlo, and by the use of classical density-functional theory.Nucleation and growth of crystals from the melt impact many day-to-day occurrences and activities. These include brazing, casting and welding in metallurgy, cryopreservation of organs for medical purposes, weather conditions due to atmospheric events, and protein crystallization for structural characterization. In this work, computer algorithms and fundamental theories are advanced and applied to learn how the underlying interactions, deviations in structures, and presence of other molecules affect growth of crystals from the liquid. Learning how to control crystallization will positively impact all of the above fields.