The total mass attenuation coefficient of trichloride gadolinium has been investigated utilizing Geant4 compared with WinXCom simulation data at energies; 1-10 MeV. The simulated results are used to calculate the total cross section, atomic and electronic cross sections. The aim of this work is to characterize new materials and their interactions with radiation in order to be able for using in shielding or detection. The GdCl3 is applied for super-Kamiokande detector of neutrons. From our comparison study, it is found that the mass attenuation coefficient of GdCl3 with those of two detectors of X-ray (Si and CdTe) is very closed. Also, the total mass transfer attenuation coefficient increases as high energies increases at pairs effect production. From our comparison study, we can predict that GdCl3 can be a good detector of X-ray and concluded that this material has shown good interaction with electromagnetic radiations at high energies.

The electronic properties of both ScxGa1−xAs and ScxGa1−xN ternary alloy and superlattice systems are investigated within the first-principles full-potential linear muffin-tin orbitals method (FPLMTO) in its atomic sphere approximation (ASA) using the technique of empty spheres, which allows an accurate treatment of the interstitial regions. The phase transition from the rocksalt (B1) to the zinc blende (B3) structure is investigated and the possibility of zinc blende/zinc blende GaN/ScxGa1−xN and GaAs/ScxGa1−xAs superlattices is expected. Wide and direct gaps are found to be possible in these systems, predicting them as good candidates for optoelectronic applications.

Using the first principles method of the full potential linear augmented plane waves (FPLAPW), the structural and the electronic properties of AlBi are investigated. It is found that this compound has a small and direct semiconducting gap at Gamma. Through the quasi-harmonic Debye model, in which the phononic effects are considered, the dependences of the volume, the bulk modulus, the variation of the thermal expansion alpha, as well as the Debye temperature theta(D) and the heat capacity C-v are successfully obtained in the whole range from 0 to 30 GPa and temperature range from 0 to 1200 K. (C) 2008 Elsevier Ltd. All rights reserved.

The structural and electronic properties of the GaAs1−xBix ternary alloy are investigated by means of two first principles and full potential methods, the linear augmented plane waves (FPLAPW) method and a recent version of the full potential linear muffin-tin orbitals method (FPLMTO) which enables an accurate treatment of the interstitial regions. In particular, we have found that the maximal GaBi mole fraction x for which GaBixAs1−x remains a semiconductor is probably around x=0.5. The electronic properties of (GaAs)m/(GaBi)n quantum well superlattices (SLs) have also been calculated and it is found that such SLs are semiconductors when m is larger or equal to n.