J. Phys. IV France
Volume 118, November 2004
Page(s) 165 - 171

J. Phys. IV France 118 (2004) 165-171

DOI: 10.1051/jp4:2004118020

Sodium doped lanthanum manganites thin films: Influence of the oxygen content on the structural parameters

I. Alessandri1, E. Bontempi1, L. Sangaletti2, S. Pagliara2, L. Malavasi3, F. Parmigiani2, G. Flor3 and L. E. Depero1

1  INSTM and Laboratorio di Strutturistica Chimica, Università di Brescia, via Branze 38, 25123, Brescia (Italy)
2  INFM and Dipartimento di Fisica, Università Cattolica del Sacro Cuore, via Musei 41, 25121, Brescia (Italy)
3  INSTM and Dipartimento di Chimica-Fisica “M.Rolla", Università di Pavia, v.le Taramelli 16, 27100, Pavia (Italy)

We report the structural characterisation of La $_{\rm 1-x}$Na$_{\rm x}$MnO $_{3+\delta}$ thin films deposited by Rf-magnetron sputtering onto SrTiO3 (100) single crystal substrates. In particular, we focussed our attention on a series of samples annealed at different pO2, ranging from 1 to 10-6 atm. XRD and microRaman data show an expansion of the perovskite lattice for samples annealed in reducing conditions. This results agree with general manganite gas-solid equilibrium involving the formation of Mn4+as the oxygen content increases. For pO $_{2}\,{<}\,10^{-6}$ atm the structure rearranges because of the increasing the oxygen vacancies and the volume of the unit cell shrinks.

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