INVESTIGADORES
PRONSATO Maria Estela
artículos
Título:
The electronic structure and bonding of hydrogen pairs and other impurities at grain boundaries
Autor/es:
S. B. GESARI; M. E. PRONSATO; A. JUAN
Revista:
Current topics in colloid & and interface science
Referencias:
Año: 2003 vol. 6 p. 179 - 185
Resumen:
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The energetics and electronic structure
of H and a H-H pair in the BCC grain boundary (GB) of Fe have been
studied by ASED-MO cluster calculation. The total energy of the
cluster decreases when the H atoms are at the GB making it a possible
site for H accumulation. Some Fe-Fe bonds in the GB plane shows
a 60 % decrease in the overlap population when H is present. H-H interaction was also analyzed. S
and H impurities in GB were also studied. The results show that
impurities induce large relaxation in the GB and that the GB gives
rise to an energetically favorable zone for the H and S accumulation.
No S-H association is found and the deleterious effect of H is of much less important when compared with
S.