Study of structural, magnetic, and electrical transport properties in La1-xCuxMnO3

Ld(1-x)Cu(x)Mno(3) compounds have been prepared in single phase form for x = 0-0.20. X-ray diffraction (XRD) patterns were recorded at room temperature and these could be refined using R3c space group by employing rietveld method. The typical lattice parameters for x = 0.10 sample are a = b = 5.531 Angstrom and c = 13.352 Angstrom. dc electrical resistivity measurements were carried out below room temperature. The samples x less than or equal to 0.10 exhibit metal-insulator transitions in the temperature range (T-MI) 43-92 K. The resistivity data above T-MI could be fitted to Mott variable range hopping (Mott-VRH) model. The samples x > 0.10 could be mostly fitted to Efros-Shklovskii VRH (ES-VRH) model. Temperature variations of ac susceptibility down to 30 K were measured at an ac field amplitude of 5.3 Oe. All the above Cu doped samples exhibit paramagnetic to ferromagnetic transitions. (C) 2004 Published by Elsevier B.V.