Fermi Surface Nesting and Magnetic Structure of ErGa3

A three-dimensional mapping of the Fermi surface (FS) of the rare-earth compound ErGa 3 was determined via measurements of the angular correlation of the electron-positron annihilation radiation. The topology of the electronlike FS does show nesting properties which are consistent with the modulated antiferromagnetic structure of the system. We determine the density of states at the Fermi energy N(E F ) and the electronic contribution to the gamma constant to be N(E F )=16 states/ Ryd /cell and γ=2.7 (mJ/mol K 2 ), respectively.