In this paper, the effect of pressure, temperature and impurity on the energylevels, binding energy, linear and nonlinear optical properties of a modified Gaussianquantum dot are studied. In this regard, the finite element method is employed to solvethe single electron Schrodinger equation in the effective mass approximation with andwithout impurity at the center of the dot. In addition, the en...

We have investigated the role of transition metal impurities and oxygen vacancies in the formation of ferromagnetism in Co-doped TiO2 using LSDA+U approach which takes into account strong on-cite Coulomb correlations for electronic structure calculations. Several model systems such as supercells of rutile TiO2 with Co ion in high-spin state substituted into titanium cite and with oxygen vacanci...

We employ density functional and quantum Monte Carlo calculations to show that significant changes occur in the optical gap of fully hydrogenated nanoclusters when the surface contains impurity passivants such as atomic oxygen. Our results show that quantum confinement is only one mechanism responsible for visible photoluminescence in silicon nanoclusters and that the specific surface chemistry...

In this work, the thermal reaction of aluminum (Al) and nickel oxide (NiO) was investigated by molecular dynamics simulations. Some effective features of reaction such as reaction temperature, the reaction mechanism, and diffusion rate of oxygen into aluminum structure were studied. ReaxFF force field was performed to study the Al/NiO thermite reaction behavior at five different temperatures (5...