Research Abstracts Online
2008 - March 2009
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 water-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.
Pierre Carrier, Supercomputing Institute Research Scholar
Cesar Renato S. da Silva, Research Associate
Pedro da Silveira, Staff
Han Hsu, Research Associate
Joao Francisco Justo Filho, Department of Electrical Engineering, University of São Paulo, São Paulo, Brazil
Harish Laganathan, Graduate Student
Tao Sun, Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York
Koichiro Umemoto, Research Associate
Zhongqing Wu, Research Associate
Yonggang Yu, Graduate Student