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• Tolerance (t) and octahedral (µ) factors deduce the cubic stability of the perovskite crystal. • Negative formation energy indicates that the system is thermodynamically stable. • Ba 2 CoTaO 6 double perovskite oxide exhibits half-metallic ferromagnetism. • Electronic charge density is discussed. • Electronic, magnetic, elastic, and optical properties were calculated. In this study, the computational functionals GGA and mBj of density functional theory (DFT) were employed to explore the electronic structure of tantalum based double perovskite oxide Ba 2 CoTaO 6. Computed tolerance (t) and octahedral (µ) factors deduce the cubic stability of the perovskite crystal. Negative formation energy indicates that the system is thermodynamically stable. The elastic constants satisfy the conditions for cubic stability and the Pagh's index (B/G) evinces the brittle nature. The band structure and total density of states reveal the half-metallic nature with a 4.7 eV insulator indirect energy band gap at the Fermi level in the spin up direction. An integer-valued (4µ B) magnetic moment is observed to favor the half-metallic ferromagnetism in the double perovskite oxide Ba 2 CoTaO 6. Optical properties play a significant role in the design and functionality of optical devices and systems. In this aspect, the two parts of the dielectric function (real and imaginary) and the related parameters have been explored. The observed properties provide insights into possible applications of this system in spintronics and optoelectronics. [ABSTRACT FROM AUTHOR]

In this GGA study, electronic and magnetic properties were investigated with the implementation of the FP-LAPW method within the framework of DFT. Resulting compounds Ag0.125Sr0.875O and Au0.125Sr0.875O were formed by substituting transition metal atoms silver and gold in strontium oxide with 12.5% concentration. Formation energy values show the compounds are stable in the ground state. Volume optimization curves predict the doped compounds are stable in the ferromagnetic phase. Total DOS and band structure plots display half-metallicity at the Fermi level, and also magnetic moment was found in the supercells. [ABSTRACT FROM AUTHOR]

Abstract Full Potential Linearised Augmented Plane Wave (FP-LAPW) method was used to investigate the electronic and magnetic properties of NiO doped with Hf and Ta within the frame work of density functional theory (DFT). NiO is found to be stable in rock salt structure. NiO shows conducting characteristics for the lattice constant of 4.155 Å. Doping Hf and Ta in the metallic super cell of NiO separately in the doping concentration of 12.5%, the compounds Hf 0.125 Ni 0.875 O and Ta 0.125 Ni 0.875 O are formed. These compounds of Hf 0.125 Ni 0.875 O and Ta 0.125 Ni 0.875 O are predicted to exhibit stability in the ferromagnetic phase. The density of states and band structure plots predict that these compounds exhibit half metallic character with formation of energy gap in one of the spins at the Fermi level. The total spin magnetic moments found in these compounds are 12.00689 μ B and 10.97628 μ B. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

• GGA and FP-LAPW methods. • TiHfOsX(X=Al,Ga,In) compounds are stable in ground state because of negative formation and cohesive energy values. • Compounds exhibit ductile and anisotropic nature. • Compounds found to be stable in ferromagnetic state. • Half-metallic ferromagnetism is predicted. Investigation of structural, elastic, electronic and magnetic properties of new quaternary TiHfOsX(X = Al,Ga,In) compounds were performed by using density functional theory approach. The calculations reveal that the quaternary compounds exhibit half-metallic ferromagnetism and follow the Slater Pauling rule (M T = A T − 18) as the magnetic moment in each cell is around 1 μ B. In the aspect of stability formation energy and cohesive energy of quaternary compounds were calculated and have been found to be stable in ground state. Also, energy versus volume curves predict that the compounds are stable in ferromagnetic state. The elastic constants were calculated which exhibits the compounds are mechanically stable by satisfying the condition of stability. The parameters (bulk modulus, shear modulus, Young's modulus, Poisson's ratio, and anisotropic factor) were determined and a ductile characteristic has been predicted in all three quaternary compounds. The predicted results propose the compounds could be good candidates for spintronics applications. [ABSTRACT FROM AUTHOR]

• Full potential-linearised augmented plane wave (FP-LAPW) method. • Cohesive energy and formation energy. • Doping of 3d transition metal atoms Ti and Cu in non-magnetic SrO to exhibit half-metallic ferromagnetism. • Structural, electronic, magnetic and elastic properties were calculated. Full potential linearized augmented plane wave method is used to study the structural, electronic, magnetic and elastic properties of SrO doped with d-block atoms titanium and cupper using DFT technique. Ti 0.125 Sr 0.875 O and Cu 0.125 Sr 0.875 O super cells were constructed by doping 3d transition metal atoms Ti and Cu with 12.5% of concentration in SrO host compound. Cohesive and formation energies were calculated which indicates the stability of the compounds. For magnetic stability, volume optimization was performed which revealed that compounds are stable in ferromagnetic phase. Elastic parameters were determined to see the hardness and stiffness of the compounds. It has been predicted that compounds are brittle and anisotropic in nature. Analysis of DOS and band structure reveals the half-metallic characteristic of the compounds. Resulting supercells are ferromagnetic with a hundred percent spin polarization carrying magnetic moment 2.00276 μ B and 0.99455 μ B respectively. Prediction of half-metallic ferromagnetism with spin polarization makes the compounds could be used for spintronics applications. [ABSTRACT FROM AUTHOR]

Using the First Principles calculations within the frame work of density functional theory (DFT) the structural, electronic and magnetic properties were determined. Co-doping of halogen atoms in the host MgO with 12.5% concentration was performed and the half-metallicity property was investigated. It is very interesting that co-doping of halogen atoms in the host MgO plays a vital role in exhibiting the half-metallic nature of the super cells Cl 0.125 Mg 0.875 Br 0.125 O 0.875, Cl 0.125 Mg 0.875 I 0.125 O 0.875 and Br 0.125 Mg 0.875 I 0.125 O 0.875. Energy band gaps were found in spin up (majority) direction at the Fermi level which reveals the half-metallicity of the compounds. Super cells were found stable in the ferromagnetic phase as compared to the non-magnetic phase. Lattice constants and equilibrium energies were calculated after volume optimization was carried out. In super cells, the halogen atoms which replace the Mg atoms contributes in producing magnetic moment but which replace O atoms having a negative impact on a total spin magnetic moment. Moreover, the contribution to create a total spin magnetic moment in the super cells is due to Mg atoms and O atoms. Image 1 • Co-doping of halogen atoms in mgo exhibit half-metallic ferromagnetism. • Structural properties. • Electronic properties. • Magnetic properties. • Application in spintronics. [ABSTRACT FROM AUTHOR]

Based on density functional theory (DFT), we present the structural, electronic, magnetic and half-metallic properties of M x Sc 1-x P (M = Cu, Zn; x = 0.125, 0.25, 0.375) by using the full potential linearized augmented plane wave (FP-LAPW) method. ScP in zinc blende structure in the undoped state exhibits semiconducting properties. To investigate the changes in electronic and magnetic properties, supercells created used different parameters and dimensions are doped with 3d10 based transition metal impurities. By doping the impurities Cu and Zn in different concentrations, half-metallic ferromagnetic properties are observed in Cu 0.125 Sc 0.875 P and Zn 0.125 Sc 0.875 P. At reduced volume, Cu 0.25 Sc 0.75 P and Zn 0.25 Sc 0.75 P also exhibit half-metallic properties in the ferromagnetic phase. The GGA + U method also confirms the half-metallic behavior of these compounds. The ternary MScP and quaternary MSc 2 P (M = Cu, Zn) are observed to be stable in the non-magnetic phases and exhibit metallic properties. M x Sc 1-x P (M = Cu, Zn; x = 0.125, 0.25) have negative cohesive energies, 100% of spin polarization at the E F , magnetic moments of integer values and exhibit half-metallic properties, thus providing a platform to the experimentalists in synthesizing them for spintronics technology. • ScP in zb phase exhibits semi-conducting properties. • Cu and Zn in 12.5%, 25% and 37.5% concentration are doped in the supercell Sc 8 P 8. • Cu 0.125 Sc 0.875 P and Zn 0.125 Sc 0.875 P exhibit half-metallic ferromagnetism. • At reduced volume Cu 0.25 Sc 0.75 P and Zn 0.25 Sc 0.75 P show a transition from AFM to Ferromagnetic phase. • ScP doped with Cu has larger magnetic moments than ScP doped with Zn. [ABSTRACT FROM AUTHOR]

Field experiments were carried out at Mountain Livestock Research Institute (MLRI), Manasbal, Sher-e-Kashmir University of Agricultural Sciences and Technology Kashmir, India to study the direct and residual effect of different rates of organic and chemical sources of nutrients on fodder sorghum-fodder oat cropping sequence during Kharif 2008, 2009 and rabi 2008-09, 2009-10. Application of FYM @ 25tonnes recorded higher green fodder yield of sorghum than rest of treatments. The physical optimum dose of direct+residual effect of FYM on fodder sorghum-fodder oat sequence was 25.49 t ha-1 and economic optimum dose 12.63 t ha-1. Applying 120, 80 and 30 (N, P2O5, K2O kg ha-1) was found superior in green fodder yield than rest of treatments. However, physical optimum dose due to direct +residual effect of N, P2O5 and K2O on fodder sorghum-fodder oat was 134.19, 67.07 and 33.54 kg ha-1 and mean total economic optimum dose was found to be 128.0, 64.19 and 32.62 NPK kg ha-1 respectively. [ABSTRACT FROM AUTHOR]

DFT + U study was carried out on the electronic properties of Palladium oxide (PdO) in the ground state to investigate half metallic ferromagnetism using Hubbard Model. A Full Potential Linearized Augmented Plane Wave (FP-LAPW) method is employed to investigate the electronic properties of PdO. Using Generalized Gradient Approximation (GGA) method, electronic properties such as density of states (DOS) and band structure plots have been plotted. A mixed phase transition between paramagnetic and ferromagnetic states has been observed to exist for this compound. Hybrid functional is used to compare the energy band gap and magnetic moments with that of PBE functional. In GGA method, DOS and band structure plots of PdO predict the metallic characteristics in both the spins, whereas in GGA + U method, half metallic ferromagnetism is predicted at the Hubbard potential (U = 5 eV and 6 eV). • DFT + U study(Hubbard model). • Phase transition between para and ferromagnetic states. • Electronic properties. • Half metallic ferromagnetism. • Application in spintronics. [ABSTRACT FROM AUTHOR]