Displacement in MgO (run time 23 sec)

Dynamics simulation of defect propagation in MgO.
displacement in mgo (run time 23 sec)
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Project Summary

This movie depicts the collision sequence of a Mg "primary knock-on atom" (PKA) in a cubic MgO crystal. The red and white spheres represent the Mg and O ions, respectively. In this Molecular Dynamics simulation a Mg atom is given a specified amount of kinetic energy in a specific crystallographic direction, This atom is the PKA. For this particular case, the PKA is seen to leave its original lattice site, leaving behind a vacancy. The Mg ion collides with other ions, thereby reducing its own momentum. At some point it gets "trapped" in the lattice site of another Mg ion. Meanwhile, the secondary Mg ion has enough momentum to travel away from its initial site until it too has lost sufficient momentum to eventually become trapped in an interstitial position. The end result is the formation of a Frenkel defect where the vacancy and interstitial are several Ångstroms apart. A large amount of the kinetic energy is dispersed via an outgoing shock wave (thermal dispersion).

Visualization produced by D. R. Jones, K. A. Perrine, Pacific Northwest National Laboratory.

Citation:
Contact:Byeongwon Park (Byeongwon.Park@pnl.gov), L. Rene Corrales (Rene.Corrales@pnl.gov), William J. Weber (Bill.Weber@pnl.gov)
File Size (Bytes):1674552