CEA/Grenoble, INAC/SPSMS-MDN, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France.
Phys Rev Lett. 2009 Dec 31;103(26):267204. doi: 10.1103/PhysRevLett.103.267204. Epub 2009 Dec 29.
The Fe3+ lattice in the Bi2Fe4O9 compound is found to materialize the first analogue of a magnetic pentagonal lattice. Because of its odd number of bonds per elemental brick, this lattice, subject to first neighbor antiferromagnetic interactions, is prone to geometric frustration. The Bi2Fe4O9 magnetic properties have been investigated by macroscopic magnetic measurements and neutron diffraction. The observed noncollinear magnetic arrangement is related to the one stabilized on a perfect tiling as obtained from a mean field analysis with direct space magnetic configuration calculations. The peculiarity of this structure arises from the complex connectivity of the pentagonal lattice, a novel feature compared to the well-known case of triangle-based lattices.
在 Bi2Fe4O9 化合物中，Fe3+晶格被证实是第一个具有磁五重晶格特性的类似物。由于每个基本砖块的键数为奇数，因此这种晶格在受到第一近邻反铁磁相互作用时容易产生几何失配。通过宏观磁测量和中子衍射研究了 Bi2Fe4O9 的磁性质。观察到的非共线磁排列与通过直接空间磁构型计算进行的平均场分析所获得的完美平铺上稳定的磁排列有关。这种结构的特殊性来自于五重晶格的复杂连接，与基于三角形的晶格的已知情况相比，这是一个新的特点。
