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Finite temperature molecular dynamics study of unstable stacking fault free energies in silicon

We calculate the free energies of unstable stacking fault (USF) configurations on the glide and shuffle slip planes in silicon as a function of temperature, using the recently developed Environment Dependent Interatomic Potential (EDIP). We employ the molecular dynamics (MD) adiabatic switching method with appropriate periodic boundary conditions and restrictions to atomic motion that guarantee stability and include volume relaxation of the USF configurations perpendicular to the slip plane. Our MD results using the EDIP model agree fairly well with earlier first-principles estimates for the transition from shuffle to glide plane dominance as a function of temperature. We use these results to make contact to brittle-ductile transition models.Comment: 6 pages revtex, 4 figs, 16 refs, to appear in Phys. Rev.

El comercio azucarero de La Española en el siglo XI/I. Presión rnonopolística y alternativas locales.

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Hombres y ganados en la tierra del oro: Comienzos de la ganadería en Indias.

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El trigo en la ciudad de México. Industria y comercio de un cultivo importado (1521 - 1564)

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Trigo y poblamiento en La Española durante la segunda mitad del siglo XVI.

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La ganadería vacuna en la isla Española (1508 - 1587)

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El orden natural y esencial de las sociedades políticas

Según Palau Justo Linda Calle y Zocrar es seud. de Juan del Castillo Carro

Comparison between classical potentials and ab initio for silicon under large shear

The homogeneous shear of the {111} planes along the direction of bulk silicon has been investigated using ab initio techniques, to better understand the strain properties of both shuffle and glide set planes. Similar calculations have been done with three empirical potentials, Stillinger-Weber, Tersoff and EDIP, in order to find the one giving the best results under large shear strains. The generalized stacking fault energies have also been calculated with these potentials to complement this study. It turns out that the Stillinger-Weber potential better reproduces the ab initio results, for the smoothness and the amplitude of the energy variation as well as the localization of shear in the shuffle set