The location of carbon and hydrogen in a Fe-alpha divacancy

S. SIMONETTI; L. MORO; G. BRIZUELA; A. JUAN

International Journal of Hydrogen Energy

Año: 2006 vol. 31 p. 1318 - 1325

The location of a carbon and two hydrogen atoms in an alpha-Fe divacancy is analysed using a tight-binding theoretical method. Calculations were performed using a Fe124 cluster. Absorption sites for the impurities near the divacancy correspond to local energy minima configurations. Fe atoms first neighbours to H atoms weaken their metallic bond. The decohesion of Fe–Fe bonds could be associated to H embrittlement. The C atoms almost do not affect the Fe–Fe bond strength. Fe–C and Fe–H bonds are formed mainly with Fe 4s orbitals. There is no bonding between C and H atoms but some H–H interaction is observed.