抄録
Electronic structure is calculated for LaSn3 by a self-consistent relativistic APW method with the one-electron potential in the local-density approximation. LaSn3 is a reference for the mixed-valence compound CeSn3 in which the 4f electrons have recently been proven to be itinerant and contribute directly to the formation of the Fermi surface. Here, the relation between the Fermi surfaces of LaSn3 and CeSn3 is investigated. The main Fermi surface of LaSn3 consists of a distorted hole sphere and a network with slender arms, both of which are connected with small necks. These sheets can explain the de Haas-van Alphen effect and the high-field magnetoresistance reasonably well. The distorted hole sphere in LaSn3 and the hole sheet in CeSn3 originate from the eighth band, and look similar to each other. In CeSn3, the electron sheet exists as a result of compensation.
