Comparative study of the Fe-C-H interaction near line and point defects in iron structures

S. SIMONETTI; G. BRIZUELA; A. JUAN

SURFACE REVIEW AND LETTERS

WORLD SCIENTIFIC PUBL CO PTE LTD

Año: 2008 vol. 15 p. 221 - 226

0218-625X

The Fe-C-H interaction near defects in iron structures was studied using qualitative structure calculations in the framework of the atom superposition and electron delocalisation molecular orbital (ASED-MO). Calculations were performed using three Fe clusters to simulate an edge dislocation, a divacancy; both in bcc iron and a stacking fault in an fcc iron structure. In all cases, the most stable location for C atom inside the clusters was determined. Therefore, and H atom was approximated to the minimum energy region where the C atom resides. The total energy of the cluster decreases when the C atom is located near the defects zone. In addition, the presence of C in the defects zone makes no favourable the H accumulation. The C acts such as expeller of H in a way that reduces the hydrogen Fe-Fe bonds weakening.