Magnetoresistance and Ferromagnetism in Disordered LaCu0.5Mn0.5O3 Perovskite

详细信息    查看全文

• 作者：Raquel Cort茅s-Gil ; M. Luisa Ruiz-Gonz谩lez ; Jos茅 M. Alonso ; Mar Garc铆a-Hern谩ndez ; Antonio Hernando ; Jos茅 M. Gonz谩lez-Calbet
• 刊名：Chemistry of Materials
• 出版年：2013
• 出版时间：May 28, 2013
• 年：2013
• 卷：25
• 期：10
• 页码：2100-2108
• 全文大小：526K
• 年卷期：v.25,no.10(May 28, 2013)
• ISSN：1520-5002

文摘

Magnetoresistance (MR) in half doped copper LaCu_0.5Mn_0.5O₃ manganese related perovskite, synthesized by means of a soft chemistry pathway, is reported. Characterization by means of Rietveld refinement from powder X-ray diffraction data, SAED, HREM, and EELS indicates a random occupation of Cu²⁺ and Mn⁴⁺ at the octahedral sites of an orthorhombic perovskite lattice. This disordered situation is in agreement to the absence of charge ordering. LaCu_0.5Mn_0.5O₃ exhibits antiferromagnetic behavior related to Mn⁴⁺鈥揙鈥揗n⁴⁺ and Cu²⁺鈥揙鈥揅u²⁺ interactions. Ferromagnetic interactions are also evident as a consequence of a disordered arrangement of Cu²⁺ and Mn⁴⁺ over the octahedral sites, being the coexistence of these ferromagnetic superexchange interactions related to the observed MR behavior at low temperature.

Keywords:

LaCu_0.5Mn_0.5O₃; orthorhombic perovskite; magnetoresistance; superexchange interactions; ferromagnetism; antiferromagnetism