Understanding the structure of metal encapsulated Si cages and nanotubes: Role of symmetry and d-band filling

Abstract

Using ab initio calculations we study the stability of Si-based cages and nanotubes stabilized by encapsulated transition metal atoms ~TMAs!. It is demonstrated that the stabilization of these cages and nanotubes as well as their magnetic properties are strongly guided by a delicate interplay between the attainable symmetry of the system and the d-band filling of the encapsulated TMA. As a result, encapsulated TMAs of the early 3-d series lead to tubular stuctures of C6 symmetry and anti-ferromagnetic alignment between the magnetic moment of the TMA and that of the Si atoms. On the other hand, the encapsulated late 3-d elements lead to tubules of the C5 symmetry and to a ferromagnetic alignment of the metal and Si magnetic moments. Encapsulated Fe atoms ~being near the middle of the 3-d series! lead to tubular structures of either C6 or C5 symmetry. © 2003 American Institute of Physics. @DOI: 10.1063/1.1607309#

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Cite this paper

@inproceedings{Mpourmpakis2003UnderstandingTS, title={Understanding the structure of metal encapsulated Si cages and nanotubes: Role of symmetry and d-band filling}, author={Giannis Mpourmpakis and George E. Froudakis and Antonis N. Andriotis and Madhu Menon}, year={2003} }