Phase Diagram and Nucleation of Materials
The study of systems under conditions of high temperature and pressure provide a considerable challenge both theoretically and experimentally. However, much can be learned using methods that have their root in the work of Aneesur Rahman at Argonne. We illustrate present-day capabilities with two examples taken from important areas of materials science for which Rahman had a keen interest. First, we shall show how the phase diagram of materials can be predicted with ab-initio accuracy focusing on the example of alkali metals whose melting line has a surprising reentrant behavior as a function of pressure. Second, we shall study the crystal growth of urea from liquid solutions showing how the effect of the solvent and of appropriate additives affects the crystal growth and how the resulting crystal shape can be predicted.
Dr. Michele Parrinello is a professor of Computational Sciences at the Swiss Federal Institute of Technology / Die Eidgenössische Technische Hochschule (ETH) in Zürich, Switzerland, and at the Università della Svizzera Italiana / University of Italian Switzerland in Lugano, Switzerland.
He is known for his numerous technical innovations in the field of atomistic simulations. He introduced with Roberto Car ab-initio molecular dynamics, known as the Car-Parrinello method, defining the beginning of a new era of electronic structure calculation and molecular dynamics simulations. He is also known for the Parrinello-Rahman method, which allows crystalline phase transitions to be studied by molecular dynamics. Recently, Parrinello has introduced metadynamics for the study of rare events and the calculation of free energies.