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We have synthesized thin films of Co1−xMgxFe2O4 (x = 0, 0.4, 0.6, 0.8, 1) on transparent conducting indium tin oxide (ITO) coated glass substrate by pulsed laser deposition method. The structural properties of the grown films were analyzed by the X-ray diffraction and Raman spectroscopy, which suggest the single phase growth of these films. Raman spectra revealed the incorporation of Mg ions into CoFe2O4 lattice and suggest that the Mg ions initially go both to the octahedral and tetrahedral sites upto a certain concentration. For higher concentration, Mg ions prefer to occupy the tetrahedral sites. [ABSTRACT FROM AUTHOR]

We have studied spin dependent electron momentum density in CoGa0.3Fe1.7O4 at 300 K using magnetic Compton spectroscopy. It is observed that major contribution to total spin moment mainly arises from Co ions while itinerant electrons show negative polarization. Orbital contribution has been deduced by comparing the magnetic Compton spectroscopy with the magnetization data. It is revealed that the anisotropy in magnetization in the system increases with the Ga doping. [ABSTRACT FROM AUTHOR]

N-doped TiO2 nano powders were prepared by sol-gel solution combustion method. The influence of different fuels (urea and citric acid) used in obtaining N-TiO2 nano particles in similar conditions (heat treatment, amount of precursors) has been investigated. The growth of different phases of TiO2 (anatase and rutile) is strongly affected by the ligands and the dehydration reaction. Reduction in the band gap of TiO2 and features observed in theXPS spectra confirm the incorporation ofN into TiO2 matrix. [ABSTRACT FROM AUTHOR]

We present the experimental momentum density of BaTiO3 measured using 20 Ci 137Cs Compton spectrometer. The experimental Compton profile (CP) has been compared with the linear combination of atomic orbitals (LCAO) based theoretical profiles for various exchange-correlation potentials. It is found that LCAO-B3PW based CP gives a better agreement with experiment than other theoretical profiles. We have also deduced the energy bands and density of states (DOS) for BaTiO3 using LCAO-B3PW scheme. The energy bands and DOS suggest an indirect band gap in the system arising due to O-2p states of valence band and Ti-3d states of conduction band. Peculiar electronic response of this system is found to be mainly due to hybridized states of Ba-5p/5s and O-2p orbitals. [ABSTRACT FROM AUTHOR]

We present the experimental momentum density of BaTiO3 measured using 20 Ci 137Cs Compton spectrometer. The experimental Compton profile (CP) has been compared with the linear combination of atomic orbitals (LCAO) based theoretical profiles for various exchange-correlation potentials. It is found that LCAO-B3PW based CP gives a better agreement with experiment than other theoretical profiles. We have also deduced the energy bands and density of states (DOS) for BaTiO3 using LCAO-B3PW scheme. The energy bands and DOS suggest an indirect band gap in the system arising due to O-2p states of valence band and Ti-3d states of conduction band. Peculiar electronic response of this system is found to be mainly due to hybridized states of Ba-5p/5s and O-2p orbitals. [ABSTRACT FROM AUTHOR]

Valence band of anatase (001) oriented pure TiO2 and Fe doped TiO2 thin films on LAO (001) substrate grown by pulsed laser deposition is studied by using synchrotron radiation photoemission spectroscopy at Indus 1 beam line. The observed valence band spectra at different photon energies show the major contribution from the O 2p states and small contribution from the Ti 3d defect states. In Fe doped sample, a new feature has been observed at ∼2.8 eV which shows an enhancement in intensity at 56 eV corresponding to the Fe 3p→3d transition, suggesting Fe incorporation into the TiO2 matrix. [ABSTRACT FROM AUTHOR]