Abstract
A new oxide of nominal stoichiometry YCrMnO~5~ has been prepared in polycrystalline form by wet‐chemistry procedures followed by thermal treatments under high‐oxygen‐pressure conditions. This material has been characterized by X‐ray and neutron powder diffraction (NPD), magnetotransport and magnetization measurements. YCrMnO~5~ is isostructural with RMn~2~O~5~ oxides (R = rare earths); its crystal structure has been Rietveld refined from NPD data in the space group Pbam, and it contains infinite chains of(Cr,Mn)^4+^O~6~ octahedra sharing edges, linked together by (Mn,Cr)^3+^O~5~ pyramids and YO~8~ units. An important level of cationic disorder has been found between both metallic sites; the refined crystallographic formula is Y[Mn~0.47(1)~Cr~0.53(1)~]~oct~[Cr~0.37(1)~Mn~0.63(1)~]~pyr~O~5~. The magnetic susceptibility indicates the onset of magnetic ordering below T~c~ ≈ 85 K; the magnetization isotherms are characteristic of a weakly ferrimagnetic material reaching a net magnetization of0.25 μ~B~/f.u. for H = 50 kOe. Low‐temperature NPD patterns do not exhibit any additional magnetic contribution, confirming that a long‐range magnetic ordering is not fully established. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)