Research Abstracts Online
January 2009 - March 2010
University of Minnesota Twin Cities
Institute of Technology
Department of Chemical Engineering and Materials Science
PI: Renata M. Wentzcovitch, Fellow
Theory of Materials at High Pressures and Temperatures
During the last few years, the Wentzcovitch group has shown that high pressure and temperature elasticity is no longer a theoretical challenge. They have calculated the full elastic constant tensor of MgSiO3-perovskite, the most important lower mantle phase. This has allowed them to calculate seismic wave velocities of this mineral and address fundamental questions regarding the nature (temperature and composition) of the lower mantle. This type of calculation is now routine for these researchers, although it is very computationally intensive. They plan to carry out these calculations on other mantle minerals, ices, and materials used as high-pressure standards (e.g. gold, platinum, NaCl, MgO).
The group has also been investigating elasticity and the vibrational/thermodynamic properties of ordered structures of ice. This information is critical to establishing a basis for understanding pressure-induced amorphization in H2O-ice. Equations of state and phase diagrams are key to understanding the structure of the icy satellites of Jupiter, Pluto, and other planets.
The researchers are also investigating the magnetic state of materials at low temperatures. Their main interest is the investigation of conductive materials where there exists a strong relationship between magnetism and transport, and they are particularly interested in potentially novel half metal systems, such as LaCoO3.
Pedro da Silveira, Staff
Dipta Bhanu Ghosh, Research Associate
Han Hsu, Research Associate
Neal Kelly, Undergraduate Student
Maribel Nunes-Valdez, Staff
Koichiro Umemoto, Research Associate