One of the Department of Energy's goals is the development of materials
that improve the efficiency, economy, environmental
acceptability, and safety of energy generation, conversion, transmission, and
use. To develop materials that perform better at acceptable cost we need
new methods of synthesis and processing. This will require an understanding
of the atomistic basis of materials properties and behavior.
With a long history of excellence in materials research and with on-site facilities for physical and computational experimentation, ORNL is well suited to meet this challenge. Towards this goal are major problems involving microstructure (independent of magnetism), magnetism (independent of microstructure), giant magneto-resistance, and thermal properties.
ORNL Solutions:A number of different first-principles techniques, including tight-binding molecular dynamics (TBMD), an iterative pseudopotential (IP) method, and the locally self-consistent multiple scattering (LSMS) method, are used to perform fundamental studies of the atomistic, electronic, and magnetic structure of microstructural defects in metals and semiconductors that involve the interactions between large numbers of atoms (TBMD 20,000 atoms, IP > 200, LSMS 250 to 3000 atoms). In addition we are developing spin dynamics based on both model Hamilitonians and (local) spin density calculations as a fundamental theory of the magnetic properties of metals and alloys.
The availability of powerful and accurate first-principles techniques permits the study of quantum interatomic interactions on a length scale not previously accessible, opening up the possiblity of relating these fundamental interatomic interactions to the strength, ductility, transport and magnetic properties of materials. Applied to magnetic materials, these techniques should help establish the foundations for understanding the relationship between the technical magnetic properties (permeability, coercivity, remenance) of magnets and microstructure.
Check it out:
M4GC home page (http://oldpc.ms.ornl.gov/~gms/M4home.html)
new Gordon Bell entry (1998)
contact: Bill Shelton