Hybridization Mechanism for Cohesion of Cd-based Quasicrystals
Abstract
Cohesion mechanism of cubic approximant crystals of newly discovered binary quasicrystals, CdM (M=Yb and Ca), are studied theoretically. It is found that stabilization due to alloying is obtained if M is an element with low-lying unoccupied states. This leads to conclusion that the cohesion of the Cd-based compounds is due to the hybridization of the states of Yb and Ca with a wide band. %unlike known stable quasicrystals without transition elements %such as Al-Li-Cu and Zn-Mg-RE (RE:rare earth). Although a diameter of the Fermi sphere coincides with the strong Bragg peaks for Cd-Yb and Cd-Ca, the Hume-Rothery mechanism does not play a principal role in the stability because neither distinct pseudogap nor stabilization due to alloying is obtained for isostructural Cd-Mg. In addition to the electronic origin, matching of the atomic size is very crucial for the quasicrystal formation of the Cd-based compounds. It is suggested that the glue atoms, which do not participate in the icosahedral cluster, play an important role in stabilization of the compound.
Cite
@article{arxiv.cond-mat/0012485,
title = {Hybridization Mechanism for Cohesion of Cd-based Quasicrystals},
author = {Yasushi Ishii and Takeo Fujiwara},
journal= {arXiv preprint arXiv:cond-mat/0012485},
year = {2009}
}
Comments
4 pages, 2 figures