Abstract
Electron density distributions were obtained using the maximum entropy method with synchrotron radiation powder data. In the metallic , metallic bonding was observed for the icosahedral cluster with central Re atom. In the nonmetallic approximant, covalent bonds were found in the electron density distribution of the Mackay icosahedral cluster without central atom. Rather than the Hume-Rothery mechanism, the covalency of Al (Si) icosahedron and that between Al (Si) and Mn atoms is considered to be the origin of the pseudogap and nonmetallic behavior of .
- Received 24 February 2000
DOI:https://doi.org/10.1103/PhysRevLett.85.3468
©2000 American Physical Society