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Electronic and Optical Studies of Coexisting 5- and 6-Atom Rings in Tetrahedral a-C

Published online by Cambridge University Press:  18 March 2011

R.M. Valladares
Affiliation:
Depto. de Física, Facultad de Ciencias-UNAM, Apartado Postal 70-542, México, D.F., 04510, MEXICO
A.G. Calles
Affiliation:
Depto. de Física, Facultad de Ciencias-UNAM, Apartado Postal 70-542, México, D.F., 04510, MEXICO
M.A. Mc Nelis
Affiliation:
Apartado Postal 70-464, México, D.F., 04510, MEXICO
Ariel A. Valladares
Affiliation:
Instituto de Investigaciones en Materiales-UNAM, Apartado Postal 70-360, México, D.F., 04510, MEXICO
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Abstract

We simulate both the amorphous cluster a-C57H52 that contains 5-atom planar rings and 6-atom boat-type rings and the crystalline cluster c-C59H60 that contains only chair-type 6-atom rings, as in the tetrahedral crystal (diamond structure). We carry out ab initio calculations using the DMol code and report the total energy, the electronic (density of states) structure and optical properties of the two types of clusters, with and without relaxation of the structures, in order to see the effect of the types of atom rings found in the amorphous structures compared to those found in the crystal structure.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

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References

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