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We have recovered the local atomic structures in a fcc Fe 46.5 Ni 53.5 solid solution near an equilibrium temperature of 600°C with an improved version of the recently demonstrated three x-ray energy ͑3͒ method. We have also reevaluated the 3 data from a Fe 22.5 Ni 77.5 crystal which significantly changed the results. Both the Warren-Cowley short-range order parameters ␣ and the first moment of the mean static displacements for Fe-Fe, Fe-Ni, and Ni-Ni pairs are recovered. Comparisons of the ␣'s from Fe 22.5 Ni 77.5 with neutron-scattering results show good agreement, and both compositions have ␣'s with a strong similarity to those from Cu 3 Au quenched from above the ordering temperature. Displacements from the average lattice of less than 0.001 Å can be recovered. For both Fe 46.5 Ni 53.5 and Fe 22.5 Ni 77.5 the average Fe-Fe first-neighbor distance of 2.564͑5͒ Å is much larger than the average derived from the lattice spacing for the alloys and is independent of concentration. However, the Ni-Ni, first-neighbor distance follows the average lattice, and the Fe-Ni first-neighbor distances are smaller than average. Both the Ni-Ni and Fe-Ni first-neighbor distances increase with Fe concentration. The relatively large and strongly chemically specific bond distances observed here may be a more meaningful concept for understanding the magnet properties of these Ni-rich alloys than the relative lesser change in

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