Dear All
My question about, that I have tried to insert an SIA interstitial into crystal structure like iron,
has maybe 2000 atoms,
what I did:
remove one atom form perfect structure and place two atoms instead which will simulate the SIA dummbel, but my problem is when I try to find how it is different in term of formation energy between <111> SIA dummbel and <110> SIA dummbel, I see the results out of expectation. since it is known that the formation energy for <110> is lower than the formation energy of <111> SIA defects but my result is opposite.
this because the once we do the simulation these interstitials reorganize into a more stable configuration. Therefore the energy that I have assigned to a particular orientation (my initial one) may correspond to a different configuration (the relaxed).
this the script I used to find the formation energy: