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Magnetic cooperative effects in small Ni-Ru clusters
F Aguilera-Granja1, R C Longo, L J Gallego
1Instituto de Física Manuel Sandoval Vallarta, Universidad Autónoma de San Luis Potosí, 78000 San Luis Potosí, México.
The Journal of Physical Chemistry. A
|October 28, 2011
Summary
This study explores nickel-ruthenium (Ni-Ru) clusters, revealing distinct structures and a magnetic cooperative phenomenon in specific compositions due to geometric and electronic interactions.
Area of Science:
- Materials Science
- Computational Chemistry
- Condensed Matter Physics
Background:
- Understanding the properties of transition metal clusters is crucial for catalysis and materials design.
- Nickel and ruthenium alloys are of interest due to their unique electronic and magnetic characteristics.
Purpose of the Study:
- To investigate the structural, magnetic, and electronic properties of Ni(7-x)Ru(x) clusters.
- To determine the influence of composition on cluster geometry and magnetism.
Main Methods:
- Ab initio calculations employing density-functional theory (DFT).
- Utilized linear combinations of pseudoatomic orbitals (LCPAO) basis sets.
- Employed nonlocal norm-conserving pseudopotentials and the generalized gradient approximation (GGA).
Main Results:
- Ni(7) and Ru(7) pure clusters exhibit octahedral and cubic structures, respectively.
- Binary Ni-Ru clusters adopt either decahedral or cubic geometries depending on composition.
- A magnetic cooperative phenomenon was observed in Ni(5)Ru(2) and Ni(4)Ru(3) clusters.
Conclusions:
- Cluster structure is sensitive to the Ni:Ru ratio.
- Ni-Ru hybridization and geometric factors drive the observed magnetic cooperative phenomenon.
- These findings provide insights into the fundamental properties of bimetallic clusters.
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