Roth Nikolaj, May Andrew F, Ye Feng, Chakoumakos Bryan C, Iversen Bo Brummerstedt
Center for Materials Crystallography (CMC), Department of Chemistry and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Langelandsgade 140, Aarhus 8000, Denmark.
Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
IUCrJ. 2018 Jun 1;5(Pt 4):410-416. doi: 10.1107/S2052252518006590. eCollection 2018 Jul 1.
Frustrated magnetic systems exhibit extraordinary physical properties, but quantification of their magnetic correlations poses a serious challenge to experiment and theory. Current insight into frustrated magnetic correlations relies on modelling techniques such as reverse Monte-Carlo methods, which require knowledge about the exact ordered atomic structure. Here, we present a method for direct reconstruction of magnetic correlations in frustrated magnets by three-dimensional difference pair distribution function analysis of neutron total scattering data. The methodology is applied to the disordered frustrated magnet bixbyite, (Mn Fe )O, which reveals nearest-neighbor antiferromagnetic correlations for the metal sites up to a range of approximately 15 Å. Importantly, this technique allows for magnetic correlations to be determined directly from the experimental data without any assumption about the atomic structure.
受挫磁体系统展现出非凡的物理特性，但其磁关联的量化对实验和理论而言都是一项严峻挑战。目前对受挫磁关联的认识依赖于诸如反向蒙特卡罗方法等建模技术，而这些技术需要有关精确有序原子结构的知识。在此，我们提出一种通过对中子全散射数据进行三维差分对分布函数分析来直接重建受挫磁体中磁关联的方法。该方法应用于无序受挫磁体方铁锰矿（MnFe）₂O₃，结果表明金属位点的最近邻反铁磁关联范围可达约15 Å。重要的是，该技术能够直接从实验数据确定磁关联，而无需对原子结构做任何假设。
