Using the first principles "full-potential linearized augmented plane-wave method" based on density functional theory, structural and electronic properties of the dihydride TiFeH 2 was investigated. This intermetallic hydride -65 Cmmm space group-with moderate hydrogen storage (1.8-1.9 % Wt.) has an orthorhombic structure. The stability analysis and total energy were calculated using the general gradient approximation (GGA). We have investigated in the ground state the lattice parameters, bulk modulus, electronic structure and formation energy of TiFeH 2 hydride. Total and partial DOS analysis show that the TiFeH 2 hydride has a metallic character. Iron below the Fermi level is the main contributor to bonding manifold whereas anti-bonding titanium states dominate above. The hybridization between iron 3d and hydrogen 1s states appear to be the strongest. Electron density reveals that a relatively high electron density extends from the hydrogen atom site to the iron atom site, but not to the titanium atom site. Formation energy values indicate that the TiFeH 2 system is more hydrogen reversible compared with TiFeH.

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This paper is based on the study of the emitted radiation by electrical discharge plasma, caused in the helium a pressure of 4.8 Torr, a power MW of 108W. The study numerical model allows the identification of several spectral lines. With the Boltzmann method the study have calculated the electronic temperature (Te=3.23eV), it corresponds to the classification scale of plasmas. The application of the Saha law gives the electronic density of the electrical discharge plasma (Ne=3.67 10 13 cm-3). The calculated theoretical spectra are in good agreement with the experimental ones.

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This paper aims to numerical study of the experimental spectrum, in the context of the diagnosis of solid materials by spectroscopy; the resulting spectrum of fluorine plasma has beenanalyzed. The plasma is generated after the sublimation of the solid sample the fluorine by Laser Induced Breakdown Spectroscopy (LIBS technique). The theoretical spectra and the electronic temperature of a obtained plasma have been calculated, this temperature (1.92 eV) is well matched to the laboratory plasma criteria. The main results also are showed that the resulting medium consisted of 96.63% Calcium and 3.36% Fluor.