The first part of this article concerns the thermodynamics of point defects. In the traditional analysis of reactions in which point defects are involved, point defects are assumed to be ideally diluted, which leads to familiar mass-actiontype equations. In this article, situations in which deviations from ideal mass-action-type behavior occur are investigated by evaluating the influence of def...

This work reexamines the insertion of O atoms in L10 γ-TiAl system using first-principles calculations and thermodynamic modeling independent point defect approximation. It includes a study intrinsic defects, many alloying elements (more than twenty were considered), as well their interaction with oxygen. The formation complex defects composed either vacancies, anti-sites or solute is then stud...

introduction: infective endocarditis (ie) causes serious complications in patients. congenital heart disease (chd) is an important underlying condition in children. case presentation: a 6-year-old girl with ventricular septal defect (vsd) was presented. echocardiography revealed large vegetation in right ventricular outflow tract near the pulmonary valve. the patient showed clinical symptoms of...

We investigated the interaction of intrinsic point defects (vacancies and self-interstitials) with a partial dislocation in silicon. Using a combination of zero-temperature ab initio total energy calculations with finite temperature free-energy calculations based on an interatomic potential, we obtained energies for the relevant core defects. The formation energies of vacancies and interstitial...

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Vacancies, interstitials, and Frenkel pairs are considered to be the basic point defects in silicon. We challenge this point of view by presenting density functional calculations that show that there is a stable point defect in silicon that has fourfold coordination and is lower in energy than the traditional defects.

The reorientation of the point-defect pailformed in CaFz crystals by substitutional Gd-lt and interstitial F ions has been studied using EPR lifetime broadening measurements and dielectric and anelastic relaxation studies at temperatures between liquid N2 and room. The GdF3 concentration ranged from 0.01 to 0.3 mole percent. The crystals were annealed in an atmosphere of He and H F at temperatu...

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Lattice defects generated by radiation damage can diffuse to grain boundaries (GBs) and be annihilated at GBs. However, the precise role of GBs in annihilating the segregated defects remains unclear. Here, we employed multi-scale models to determine how interstitials are annihilated at small-angle tilt GBs (STGBs) in SiC. First of all, we found the pipe diffusion of interstitials in STGBs is sl...