EN
We have synthesized Cu-substituted (Au,Cu)-Al-Yb quasicrystals in order to investigate the relationship between the quasilattice constant and the magnetic property. The quasilattice constant a_{R} is found to decrease as Au is replaced by Cu, and the maximum reduction of 2.18% in a_{R} was observed for x=0.60 in (Au_{1-x}Cu_x)_{49}Al_{34}Yb_{17}. Magnetic measurements of (Au_{1-x}Cu_x)_{49}Al_{34}Yb_{17} (x=0, 0.10, 0.20, 0.50) show that the intermediate-valence state of Yb persists in all the studied compositions. The effective magnetic moment is found to depend on r̅/a_{R} rather than on the quasilattice constant a_{R}. This suggests that r̅/a_{R} can be regarded as a measure of the chemical pressure induced on the Yb atoms.