Coupled structural and magnetic properties of ferric fluoride nanostructures part I: A Metropolis atomistic study

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:322

Article

Fongang, B.¹  Labaye, Y.¹  Calvayrac, F.¹  Greneche, J. M.¹  Zekeng, S.² 

[1] Univ Maine, Lab Phys Etat Condense, CNRS, IRIM2F,UMR 6087,FR 2575, F-72085 Le Mans 9, France

[2] Univ Yaounde 1, Dept Phys, Mat Sci Lab, Yaounde, Cameroon

关键词: Nanostructuration;    Iron fluoride;    Grain boundary;    Metropolis;    Magnetic frustration;   

DOI  :  10.1016/j.jmmm.2010.04.046

来源: Elsevier

【 摘 要 】

A modified Metropolis atomistic simulation is proposed to model the structure of grain boundaries (GBs) and interfaces in ionic nanostructured systems and is applied to the magnetically interesting case of iron trifluoride(FeF(3)). We chose long-range inter atomic potentials adjusted on experimental results and adapted a previously established Monte Carlo scheme consisting of various modifications of the simulated annealing/Metropolis algorithm. Atomic structures of twisted and tilted GBs as a function of the relative disorientation of the grains have been achieved yielding close to experimentally measured properties. This approach takes into account the structure of the grains far from the interface in order to constrain the relative orientation of the grains, with out any periodic boundary conditions. One concludes that along-range Coulombic fall off of the interatomic potentials is necessary to obtain GB structures presenting a correct local topology but with a smooth transition from crystalline to amorphous states. The structural features are finally discussed in terms of topological aspects and local magnetic structure. (C) 2010 Elsevier B.V. All rights reserved.

【 授权许可】

Free