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A single crystal of at. % Al aged within the ␣ phase at 673 K was investigated by diffuse x-ray scattering. The separated short-range-order scattering is only weakly modulated and shows two types of diffuse maxima simultaneously, at 2k F 110 ͑where k F is the Fermi wave number along ͗110͒͘ and at 1/2,1/2,1/2 positions.Such a topology has previously been observed only in the Cu-Pt system. A detailed analysis of nearestneighbor configurations, however, exhibits large differences between the two systems; the data suggest the A 5 B structure as a possible ground-state structure of the fcc Ag-Al lattice, i.e., none of the structures observed in the Cu-Pt system. For this structure an order-disorder transition temperature of ϳ135 K is estimated on the basis of Monte Carlo simulations with effective pair-interaction parameters of the first 18 shells.