Atomic structure determination, electronic structure calculations and interpretation of electron transport properties of various 1/1-1/1-1/1 approximants

The atomic structure of various 1/1– 1/1– 1/1 approximants has been extensively studied in the last decade to bridge the gap to that of the corresponding quasicrystal. Reliable information about electronic states in their valence bands has also been accumulated by using the atomic structure determined theoretically and experimentally. In this article, we have classified 1/1– 1/1– 1/1 approximants into three groups in terms of the structure type (P or F) and space group (Im or P m) and discussed characteristic features of both atomic and electronic structures of 1/1– 1/1– 1/1 approximants in each group. The electrical resistivity behaviour is then discussed on the basis of the atomic and electronic structures thus determined.