How to affect stacking fault energy and structure by atom relaxation

By a simulated annealing method with a parameterized tight-binding potential, the properties of structure and energy of a generalized stacking fault are investigated. It is shown that for metal Pd, the second-layer spacing from the stacking fault plane expands initially and then contracts with the variation of the stacking fault variable from 0 to 1. The effect of atom relaxation on stacking fault energy is shown to be small. For another metal Pt, the second-layer spacing contracts and the effect of atom relaxation on the stacking fault energy is found to be obvious. In addition, the calculated stacking fault energy is in agreement with experimental results for the two metals.