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Density functional theory and quasi-harmonic Debye model has been used to study the thermodynamic properties of 2H-CuInO2. At the optimized structural parameters, pressure (0 to 80 GPa) dependent variation in the various thermodynamic properties, i.e. unit cell volume (V), bulk modulus (B), specific heat (Cv), Debye temperature (ӨD), Grǘneisen parameter (γ) and thermal expansion coefficient (α) are calculated for various temperature values. The results predict that the pressure has significant effect on unit cell volume and bulk modulus while the temperature shows negligible effect on both parameters. With increasing temperature thermal expansion coefficient increase while with increasing pressure it decreases. The specific heat remains close to zero for ambient pressure and temperature values and it increases with increasing temperature. It is observed that the pressure has high impact on Debye temperature and Grǘneisen parameter instead of temperature. Debye temperature and Grǘneisen parameter both remains almost constant for the temperature range (0-300K) while Grǘneisen parameter decrease with increasing pressure at constant temperature and Debye temperature increases rapidly with increasing pressure. An increase in Debye temperature with respect to pressure shows that the thermal vibration frequency changes rapidly. [ABSTRACT FROM AUTHOR]

Density functional theory and quasi-harmonic Debye model has been used to study the thermodynamic properties of 2H-CuInO2. At the optimized structural parameters, pressure (0 to 80 GPa) dependent variation in the various thermodynamic properties, i.e. unit cell volume (V), bulk modulus (B), specific heat (Cv), Debye temperature (ӨD), Grǘneisen parameter (γ) and thermal expansion coefficient (α) are calculated for various temperature values. The results predict that the pressure has significant effect on unit cell volume and bulk modulus while the temperature shows negligible effect on both parameters. With increasing temperature thermal expansion coefficient increase while with increasing pressure it decreases. The specific heat remains close to zero for ambient pressure and temperature values and it increases with increasing temperature. It is observed that the pressure has high impact on Debye temperature and Grǘneisen parameter instead of temperature. Debye temperature and Grǘneisen parameter both remains almost constant for the temperature range (0-300K) while Grǘneisen parameter decrease with increasing pressure at constant temperature and Debye temperature increases rapidly with increasing pressure. An increase in Debye temperature with respect to pressure shows that the thermal vibration frequency changes rapidly. [ABSTRACT FROM AUTHOR]

We computed the energy band and density of states for electronic properties while for optical properties we computed dielectric function, absorption coefficient, optical conductivity and refractive index. The origin of energy bands is interpreted in terms of density of states. The electronic transitions in energy bands are explained from frequency dependent dielectric constant. Our computed band structure predicts AgInO2 as indirect band gap semiconductor while from optical properties we have predicted importance of AgInO2 in photovoltaic applications. We also reported valence charge density for this compound. Our computed results are in better agreement with available experimental data than those of earlier theoretically reported. [ABSTRACT FROM AUTHOR]

We have studied the structural stability, electronic structure, optical properties and thermoelectric properties of doped BaHfO3 by full potential linearized augmented plane wave (FP-LAPW) method. The electronic structure of BaHfO3 doped with Sr shows enhances the indirect band gaps of 3.53 eV, 3.58 eV. The charge density plots show strong ionic bonding in Ba-Hf, and ionic and covalent bonding between Hf and O. Calculations of the optical spectra, viz., the dielectric function, refractive index and extinction coefficient are performed for the energy range are calculated and analyzed. Thermoelectric properties of semi conducting are also reported first time. The doped BaHfO3 is approximately wide band gap semiconductor with the large p-type Seebeck coefficient. The power factor of BaHfO3 is increased with Sr doping, decreases because of low electrical resistivity and thermal conductivity. [ABSTRACT FROM AUTHOR]

We computed the energy band and density of states for electronic properties while for optical properties we computed dielectric function, absorption coefficient, optical conductivity and refractive index. The origin of energy bands is interpreted in terms of density of states. The electronic transitions in energy bands are explained from frequency dependent dielectric constant. Our computed band structure predicts AgInO2 as indirect band gap semiconductor while from optical properties we have predicted importance of AgInO2 in photovoltaic applications. We also reported valence charge density for this compound. Our computed results are in better agreement with available experimental data than those of earlier theoretically reported. [ABSTRACT FROM AUTHOR]

We have studied the structural stability, electronic structure, optical properties and thermoelectric properties of doped BaHfO3 by full potential linearized augmented plane wave (FP-LAPW) method. The electronic structure of BaHfO3 doped with Sr shows enhances the indirect band gaps of 3.53 eV, 3.58 eV. The charge density plots show strong ionic bonding in Ba-Hf, and ionic and covalent bonding between Hf and O. Calculations of the optical spectra, viz., the dielectric function, refractive index and extinction coefficient are performed for the energy range are calculated and analyzed. Thermoelectric properties of semi conducting are also reported first time. The doped BaHfO3 is approximately wide band gap semiconductor with the large p-type Seebeck coefficient. The power factor of BaHfO3 is increased with Sr doping, decreases because of low electrical resistivity and thermal conductivity. [ABSTRACT FROM AUTHOR]

This paper presents structural, electronic, optical and magnetic properties of pure and Fe doped cubic Hafnia (HfO2). We used mBJ potential within FP-LAPW approximation to compute these properties. The calculated values of band gap from relaxed atomic positions and lattice parameter is in good agreement with experimental band gap. The calculation indicates that the Fe doped compound is direct transition semiconductors with half-metallic property. With the increase of Fe-doping concentration, the Fermi level shifts towards valence band. The impurity may change the property of the bond formation to some extent, and make it to have metallic bond characteristic. The total magnetic moment is mainly due to 3d states of Fe atoms and small induced magnetic moment exists due to other nonmagnetic atom, with a magnetic moment of about 4.0 µB per Fe-dopant. We have also computed and interpreted the absorption spectrum corresponding to the imaginary part of dielectric function in the range 0-40 eV. The peaks are related to the transition of electrons, which indicates internal relationship between the electronic structures and optical properties. The absorption of visible light can be enhanced after Fe doping. [ABSTRACT FROM AUTHOR]

The first principle investigation of structural, electronic, magnetic and optical properties of Ba1-xTMxS (x = 0.25) have been done using FPLAW method within the density functional theory (DFT) using generalized gradient approximation (GGA) for exchange correlation potential using two different functionals which are the PBE-sol and the modified Becke and Johnson local (spin) density approximation (mBJLDA). It was found that mBJLDA functional offer better account for the electronic structure of the Fe, Co and Ni-doped BaS. It was also observed that Fe/Co/Ni d, S p and Ba d states play a major role in determining the electronic properties of this alloy system. Investigation results shows that Ba0.75(Fe/Co/Ni)0.25S is ferromagnetic with magnetic moment of 3.72 µB, 2.73908 µB and 1.74324 µB at Fe, Co and Ni sites respectively. Complex dielectric constant ε(ω) and normal incidence reflectivity R(ω) are also been investigate for broad range of photon energies. These results are compared with the some reported existing experimental values. [ABSTRACT FROM AUTHOR]

The spin dependent momentum densities in Ni2MnSn Heusler alloy have been measured at 10 and 300 K using magnetic Compton scattering. For these measurements, we have used 182.79 keV circularly polarized synchrotron radiation at SPring8, Japan. Spin dependent electron momentum densities are analyzed in terms of Mn 3d, Ni 3d and itinerant electrons to calculate their role in formation of net spin moment. Magnetic moments at different sites of constituent atoms have also been compared with the present full potential linearised augmented plane wave calculations and other available data. [ABSTRACT FROM AUTHOR]

This paper presents structural, electronic, optical and magnetic properties of pure and Fe doped cubic Hafnia (HfO2). We used mBJ potential within FP-LAPW approximation to compute these properties. The calculated values of band gap from relaxed atomic positions and lattice parameter is in good agreement with experimental band gap. The calculation indicates that the Fe doped compound is direct transition semiconductors with half-metallic property. With the increase of Fe-doping concentration, the Fermi level shifts towards valence band. The impurity may change the property of the bond formation to some extent, and make it to have metallic bond characteristic. The total magnetic moment is mainly due to 3d states of Fe atoms and small induced magnetic moment exists due to other nonmagnetic atom, with a magnetic moment of about 4.0 µB per Fe-dopant. We have also computed and interpreted the absorption spectrum corresponding to the imaginary part of dielectric function in the range 0-40 eV. The peaks are related to the transition of electrons, which indicates internal relationship between the electronic structures and optical properties. The absorption of visible light can be enhanced after Fe doping. [ABSTRACT FROM AUTHOR]