Substitution Effect on the Interplane Coupling in Crednerite: the Cu1.04Mn0.96O2 Case

详细信息    查看全文

• 作者：M. Poienar ; C. Vecchini ; G. Andr茅 ; A. Daoud-Aladine ; I. Margiolaki ; A. Maignan ; A. Lappas ; L. Chapon ; M. Hervieu ; F. Damay ; C. Martin
• 刊名：Chemistry of Materials
• 出版年：2011
• 出版时间：January 11, 2011
• 年：2011
• 卷：23
• 期：1
• 页码：85-94
• 全文大小：1109K
• 年卷期：v.23,no.1(January 11, 2011)
• ISSN：1520-5002

文摘

The 4%Cu for Mn substitution in CuMnO₂ decreases slightly the lattice parameters, reduces the Jahn鈭扵eller distortion of the MnO₆ octahedra, but does not change the temperature dependence of the structure, showing a C2/m to P1̅ structural transition (in the vicinity of the magnetic transition temperature). In contrast, the antiferromagnetic structure is strongly modified by the substitution, as a propagation vector k = (0 ¹/₂ 0) is evidenced for Cu_1.04Mn_0.96O₂ compared to k = (0 ¹/₂ ¹/₂) for CuMnO₂. Consequently, the interplane magnetic coupling (along the c axis) changes from antiferromagnetic in CuMnO₂ to ferromagnetic in Cu_1.04Mn_0.96O₂ without change in the antiferromagnetic arrangement of the ferromagnetic chains in the (a,b) plane. The nanostructural study points toward the existence of numerous defects at the nanoscale which justify the modeling of strains used in the refinement of the crystalline structure.