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The effect of 200 MeV Ag ion irradiation on structural, electrical transport, magnetization and low-frequency conduction noise properties of electron-doped La(sub 0.7)Ce(sub 0.3)MnO3 thin films is investigated. The as-grown thin films show c-axis epitaxial structure along with a small amount of unreacted CeO2 phase.

Abstract: The electronic, elastic and mechanical properties of eight binary B 2 – type intermetallic compounds of Ag and Au (AgX and AuX, X=Mg, Sc, Zn and Cd) have been studied systematically using first principles density functional theory within generalized gradient approximation. Ground state properties such as lattice constant (a 0), bulk modulus (B), its pressure derivative (B′) and elastic constants are calculated. The present results are in good agreement with the experimental and other available theoretical results. Poisson’s ratio (σ), Young’s moduli (E), shear moduli (GH ) and the ratio of elastic anisotropy factor (A) are also estimated. Ductility for these compounds is further analysed by calculating the ratio of B/GH and Cauchy pressure (C 12–C 44). Amongst all the intermetallics AuZn is found to be most ductile due to the presence of strong metallic bonding, and AgZn is least ductile in all the Au and Ag intermetallic compounds. [Copyright &y& Elsevier]

The structural, electrical, and magnetic properties of La 0.67 Sr 0.33 Mn 1−x Cr x O 3 (0 ≤ x ≤ 0.10) manganites have been studied by substitution of antiferromagnetic trivalent Cr ion at Mn-site. Systematic efforts have been carried out to understand the electrical resistivity behavior in the ferromagnetic metallic and paramagnetic semi-conducting phases of Cr substituted La 0.67 Sr 0.33 Mn 1−x Cr x O 3 manganites. Polycrystalline samples show a resistivity minimum at a temperature (T min ) of <40 K in the ferromagnetic metallic phase. T min shifts to higher temperatures on application of magnetic fields. The appearance of this resistivity minimum was analyzed by fittings the data according to the model that considers e-e scattering caused by enhanced Coulombic interactions. The electrical resistivity data has been best fitted in the metallic and semiconducting regime using various models. Present results suggest that intrinsic magnetic inhomogeneity like Cr 3+ ions in these strongly electron-correlated manganite systems is originating due to the existence of the ferromagnetic interactions. [ABSTRACT FROM AUTHOR]

Highlights: [•] The DFT calculations have been performed for two CuX (X=Sc and Pd) compounds. [•] The B/GH >1.75, indicating the ductile nature of the compounds. [•] The anisotropy factor, A >1, shows that the compounds are elastically anisotropic. [•] The electronic band structures reveal that CuX compounds are metallic in nature. [•] The calculated elastic constants obey the stability criterions. [Copyright &y& Elsevier]

Abstract: A theoretical study of structural, electronic, elastic, thermal and mechanical properties of nonmagnetic intermetallics YM (M=Cu, Zn and Ag), which crystallize in CsCl-type structure, is performed using first principles density functional theory based on full potential linearized augmented plane wave (FP-LAPW) method. The calculations are carried out within the generalized gradient approximation (GGA) for the exchange correlation potential. The calculated ground state properties such as lattice constants, bulk modulus and elastic constants agree well with the experiment. From energy dispersion curves, it is found that these compounds are metallic in nature. The ductility of these intermetallics is determined by calculating the bulk to shear ratio B/G H . The calculated results indicate that YAg is the most ductile amongst the present YM compounds. The results obtained are compared with the available experimental and theoretical results. The mechanical and thermal properties are predicted from the calculated values of elastic constants. [ABSTRACT FROM AUTHOR]

Abstract: We report ab initio calculations of pressure-induced structural phase transition and electronic properties of the NaCl-type actinide nitrides namely AnN (An=Np and Cm). The total energy as a function of volume is obtained using the self-consistent tight-binding linear muffin tin orbital (TB-LMTO) method by performing spin and non-spin-polarized calculations. Magnetically the AnN compounds are stable in ferromagnetic (FM) state at ambient condition. From the present study, we predict a structural phase transition from ferromagnetic (FM) NaCl-type (B1 phase) structure to ferromagnetic CsCl-type (B2 phase) structure for these in the pressure range of 80.0–50.0GPa. The pressure-induced transition is found to be first order. The band structure and density of states (DOS) are reported in both FM-B1 phase and FM-B2 phase. The ground-state properties such as magnetic moment, lattice parameter and bulk modulus are calculated and compared with the available theoretical and experimental results. [Copyright &y& Elsevier]