Nucleation, Structure and Magnetism of Transition Metal Clusters from First Principles

  • Sanjubala Sahoo
  • Markus E. Gruner
  • Alfred Hucht
  • Georg Rollmann
  • Peter Entel
Chapter
Part of the NanoScience and Technology book series (NANO)

Abstract

Properties of transition metal (TM) clusters such as structural stability, growth and magnetic properties are studied using the density functional theory (DFT). We find that for both elemental and binary clusters, different morphologies are stable for different ranges of cluster sizes. We discuss possible structural transformations namely Jahn-Teller (JT) and Mackay transformation (MT) occurring in TM clusters. While the JT-distorted cluster is stable for a Fe\(_{13}\) icosahedron, the MT-distorted structure is stable for Co\(_{13}\). For Ni\(_{13}\), however, both distortions lead to similar energies. In larger clusters, both JT and MT compete with each other, and as a result we find a higher stability for large Fe clusters with a shell wise Mackay transformation. Studies on binary Fe-Pt clusters show a segregation tendency of Pt atoms to the surfaces of the clusters. The ordered Fe-Pt icosahedral structures show enhanced stability compared to the L1\(_0\) cuboctahedron. From the studies on magnetocrystalline anisotropy (MAE) for clusters, we find that relaxed Fe\(_{13}\) and Ni\(_{13}\) have several orders of magnitude larger MAE as compared to the corresponding bulk values. However, Co\(_{13}\) does not follow this trend.

Keywords

Bimetallic Cluster Average Magnetic Moment Binary Cluster Icosahedral Structure Transformation Path 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

We thank the John von Neumann Institute for Computing, the Jülich supercomputing Center and the Center for Computational Sciences and Simulation (CCSS), University of Duisburg-Essen for computation time and support. Also Financial support was granted by the Deutsche Forschungsgemeinschaft through SFB 445.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Sanjubala Sahoo
    • 1
  • Markus E. Gruner
    • 1
  • Alfred Hucht
    • 1
  • Georg Rollmann
    • 1
  • Peter Entel
    • 1
  1. 1.Faculty of Physics and Center for Nanointegration CENIDEUniversity of Duisburg-EssenDuisburgGermany

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