NMR-STUDIES ON AMORPHOUS, ICOSAHEDRAL, AND CRYSTALLINE PHASES

We report on AL-27, Cu-63, and V-51 spin-echo spectra for the amorphous phase and icosahedral quasicrystal of the Al75Cu15V10 alloy, and Al-27, Cu-65, and Mn-55 spin spectra for the icosahedral and crystalline phases of the Al67Cu20Mn13 alloy. The line shape and peak shift reveal different local characteristics among those phases. For the Al75CU15V10 alloy, peak shifts of all constituent nuclei are more positive in the amorphous phase than in the icosahedral phase, indicating a different s-electron density. For the Al67Cu20Mn13 alloy, an as-quenched icosahedral phase transforms to a crystalline phase by heat treatment. Different peak shifts of Al-27 and Mn-55 except Cu-65 between those phases have been found. It is suggested that there are Mn atoms carrying magnetic moment and that there is no difference in the electronic structure of Cu atoms between those phases.