USE OF NEUTRON POWDER DIFFRACTION TO GAIN INSIGHT INTO COMPLEX COBALT OXIDES

AURELIO, G.

Barilohe

Workshop; Workshop on Neutron Scattering to study Magnetic, Multiferroic and Superconducting Materials; 2016

CNEA-PSI(Suiza)

Cobalt-oxide based materials have always been a focus of interest, and increasingly complex oxides are constantly emerging with attractive properties and potential applications. Because of their versatility and tunable features, which come hand in hand with their crystallographic and magnetic complexity, a profound understanding of their novel properties poses a challenge to solid-state scientists. In this talk I will overviewhow we have used neutron powder diffraction (NPD) together with complementary techniques to study some cobalt-rich oxides such as the layered perovskite compounds RBaCo 2 O 5+δ (R = rare earth, 0 < δ < 1) and the geometrically frustrated systems YBaCo 4 O 7 and CaBaCo 4 O 7 , the latter being a promising magnetoelectric compound. In our group, we tackle variables such as oxygen non-stoichiometry and cation substitutions to control the mixed valence state of Co ions and study the role of disorder. We study the influence of these variables on their physical properties, with special emphasis on crystallography and magnetic order, for which the NPD techniques have been intensively used.