Fundamental Studies of Metastable Liquids. Final Report. (June 1, 1987 through April 30, 2008)

摘要

Materials that exist under thermodynamic conditions in which the stable state is in a different state of aggregation are said to be metastable. Examples include supercooled liquids (stable state: crystal), superheated liquids (stable state: vapor), and glasses (stable state: crystal). Metastable liquids and glasses play important roles in atmospheric phenomena (cloud formation), communications (optical fibers, which are made of amorphous silica), energy technology (solar cells made of amorphous silicon), and pharmaceutical technology (preservation of labile biochemicals in glassy matrices). In spite of the importance and ubiquity of metastable liquids and glasses, fundamental questions exist on the nature of the glassy state (Is the glass transition kinetic or thermodynamic in nature. What is the microscopic origin of the extraordinary increase in relaxation times that gives rise to the glass transition), and the physical properties of metastable liquids (Does water possess a metastable critical point in the supercooled region. Why do rotational and translational motions decouple in a supercooled liquid). The goal of this project was to investigate the above fundamental questions through the use of molecular simulations and statistical mechanics.