Influence of La doping on the properties of molybdenum perovskite Sr1-xLaxMoO3 (0≤x≤0.2)

The effects of La-doping on the structural, magnetic, electrical transport and specific-heat properties in 4d perovskites Srl-xLaxMoO3 (0 <= x <= 0.2) have been investigated. The substitution of Sr ions by La ions does not change the space group of the samples, but increases the lattice parameter a (A). The resistivity p and magnetic susceptibility X decrease monotonously with the increase of x, while the electronic specific heat coefficient gamma(e) increases. The resistivity of all samples shows a T 2 dependence in the low-temperature region of 2 K < T < 125 K and a T dependence in the high-temperature range of 130 K < T < 350 K, related to the electron-electron (e-e) and electron-phonon (e-ph) scattering, respectively. The specific-heat data agrees with the classical Dulong-Petit phonon specific heat, C-cl = 3k(B)rN(A) = 124.7 J/Mol K at high temperatures and C-p (T)/T = gamma(e) + beta T-p(2) at low temperatures. These behaviors can be explained according to the decrease of the density of states (DOS) at the Fermi energy level (E-F), N(E-F). (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.