Abstract
The positron-annihilation lifetime spectra in the Al-Pd-Re alloy system, the positron-annihilation Doppler-broadening spectra by slow variable monoenergetic positron beam in and alloys, and positron-annihilation lifetime spectra by slow positron beam in were measured. These measurements indicate that every sample contains a dense distribution of structural vacancy-type sites. This result is consistent with our previous expectation of the relationship between the presence of vacant centers in clusters and the stability of icosahedral quasicrystals. Furthermore, the structural vacancy densities in icosahedral quasicrystals of and have been estimated to be and respectively.
- Received 22 October 1998
DOI:https://doi.org/10.1103/PhysRevB.59.6712
©1999 American Physical Society