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First-principle calculations were performed in the frame work of the density functional theory (DFT) using FP-LAPW method as implemented in Wien2k code to determine the structural stability, electronic and magnetic properties of Rh2CrGe1-xAlx (x = 0, 0.25, 0.50, 0.75 and 1). The results showed that for Rh2CrAl and Rh2CrGe, the Cu2MnAl-type structure is energetically more stable than Hg2CuTi-type structure at the equilibrium volume. The calculated densities of stats for Rh2CrAl and Rh2CrGe show half metallic and nearly half metallic behavior respectively. Rh2CrGe1-xAlx (x = 0.25, 0.50, 0.75) these alloys show half metallic character, and these compounds are predicted to be good candidates for spintronic applications. [ABSTRACT FROM AUTHOR]

The structural, electronic and magnetic properties of half-Heusler compounds XVSb (X = Fe, Co and Ni) are investigated by using the density functional theory with generalized gradient approximation (GGA), and Tran-Blaha modified Becke-Johnson (TB-mBJ) exchange potential approximation. It is found that the half-metallic gaps are generally reasonably widened by mBJ as compared to the GGAapproximation. The magnetic proprieties of XVSb (X = Fe, Co and Ni) are well defined within mBJ with an exact integer value of magnetic moment. The band gaps given by TB-mBJ are in good agreement with the available theoretical data. The FeVSb exhibits a semiconductor nature. The CoVSb and NiVSb present half-metallic behaviour with total magnetic moment of and 2B in good agreement with Slater-Pauling rule. These alloys seem to be a potential candidate of spintronic devices. [ABSTRACT FROM AUTHOR]

In this paper, we use the 1rst-principles calculations based on the density functional theory to investigate structural, electronic and magnetic properties of Fe2YSn with (Y = Mn, Ti and V). The generalized gradient approximation (GGA) method is used for calculations. The Cu2MnAl type structure is energetically more stable than the Hg2CuTi type structure. The negative formation energy is shown as the evidence of thermodynamic stability of the alloy. The calculated total spin moment is found as 3µB and 0µB at the equilibrium lattice constant for Fe2MnSn and Fe2TiSn respectively, which agrees with the Slater-Pauling rule of Mt = Zt -24. The study of electronic and magnetic properties proves that Fe2MnSn and Fe2TiSn full-Heusler alloys are complete half-metallic ferromagnetic materials. [ABSTRACT FROM AUTHOR]

Dynamic properties of spreading infection through a heterogeneous population are studied numerically and analytically using a dynamic variant of Watts and Strogatz Small World Network-based stochastic Susceptible-Exposed-Infectious-Removed (SEIR) epidemic model. This model includes the main realistic parameters usually characterizing transmissible diseases, such as the force of infection, latency and infection times. As far as the latency time remains smaller than that of infection, the proportion of infected individuals increases exponentially with time, otherwise an oscillatory behavior appears. This may explain the periodic behaviors in time observed by the health prevention services. It is also shown that periodic epidemiological surveys overestimate or underestimate the dynamics of infection if the survey periods do not exactly correspond to the characteristic times of the infection. Further discussion is provided on the diffusion and relaxation processes involved in this model, and their relation to the infection characteristic time. [ABSTRACT FROM AUTHOR]

We investigate the structural, electronic and magnetic properties of the full Heusler compounds Mn2YSn (Y=Mo, Nb, Zr) by first-principles density functional theory using the generalized gradient approximation. It is found that the calculated lattice constants are in good agreement with the theoretical values. We observe that the Cu2MnAl-type structure is more stable than the Hg2CuTi type. The calculated total magnetic moments of Mn2NbSn and Mn2ZrSn are 1/n; and 2/n; at the equilibrium lattice constant of 6.18 and 6.31, respectively, for the Cu2MnAl-type structure. Mn2MoSn have a metallic character in both Hg2CuTi and Cu2MnAl type structures. Thetotal spin magneticmoment obeys the Slater-Pauling rule. Half-metal exhibits 100% spin polarization at the Fermi level. Thus, these alloys are promising magnetic candidates in spintronic devices. [ABSTRACT FROM AUTHOR]

In this paper, the structural, electronic and magnetic properties of the GdSn3, CmSn3 and GdxCm1-xSn3 compounds (x = 0:25, 0:5 and 0:75) were studied using the full-potential linearized augmented plane wave method, within the generalized gradient approximation+U. The ground-state properties are determined for the bulk materials GdSn3, CmSn3 and GdxCm1-xSn3 crystallized in AuCu3-type structure. The calculated structural, electronic and magnetic properties of GdSn3 compound are in good agreement with the existing experimental and theoretical data. It is found that the most stable magnetic con1gurations of both compounds CmSn3 and GdSn3 are anti-ferromagnetic type A (AFM-A) and have a metallic behavior. The magnetic moment found decreases with increasing the Cm composition in GdxCm1-xSn3 compounds. The results show that the GdSn3, CmSn3 and GdxCm1-xSn3 compounds share some properties, and may well be useful for spintronic applications. [ABSTRACT FROM AUTHOR]