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We present the results on atomic and lattice structure of the polycrystalline spinel ferrites system Co1-x TixFe2O4 (x = 0.0, 0.25, 0.50) synthesized by following the conventional solid-state reaction route. The observed X-ray diffraction (XRD) data confirms that all the prepared samples are indexed in cubic crystal structure (space group Fd3m). Diffraction pattern showed TiO2 phase due to presence of Ti+4 ions. Four Raman active phonon modes are observed for CoFe2O4 sample existing around 295, 462, 585, 689, cm-1 as Eg, T2g(2), T2g(3), and A1g, respectively. With 25 % Ti ion doping, the peak T2g(3) disappears, while to that T2g(1) emerges. This is an indication of presence of TiO2 phase in Co0.75Ti0.25Fe2O4 and Co0.5Ti0.5Fe2O4 ceramics. [ABSTRACT FROM AUTHOR]

Polycrystalline YBa2(Cu1-XZnX)3O7-δ samples (x=0.0 to 0.06) were studied using XRD, titration, resistivity, magnetization and XPS measurements. The O2 stoichiometry (δ) is found to change on Zn substitution which affects the normal state resistivity of the system as well as the superconducting transition temperature (TC). Interestingly, the non-magnetic Zn ions also induce local magnetic moment as confirmed from the M-H curves. It is concluded that Zn doping induced change in O2 stoichiometry and the magnetic pair breaking cause a rapid suppression in superconductivity. [ABSTRACT FROM AUTHOR]