RheoMan: a five-year, ERC-funded (Advanced Grant), project to model the rheology of the Earth's mantle

Apr 23, 2015 More about MgO General

While Marquardt & Miyagi provide evidence for an increase in strength of MgO at pressures of the uppermost lower mantle, full atomistic modeling of dislocations in MgO based on first-principles confirm the change in the dislocation core structure induced by pressure

Under increasing pressure, the core of dislocations in MgO evolves from a spreading in (110) (at low pressure) to a narrower configuration spread in (100) as pressure increases up to 100 GPa.

 

 

Calculations rely on a periodic arrangement of dislocation quadrupoles

 

see the paper just published by our group: P. Carrez, J. Godet & P. Cordier (2015) Atomistic simulations of ½<110> screw dislocation core in magnesium oxide. Computational Materials Science, 103, 250-255, doi:10.1016/j.commatsci.2014.10.019