Atomic short range order of PtV and PdV alloys

Neutron scattering experiments were performed for PtV and PdV alloys with V concentration of about 10 at.%. Although an equilibrium atomic order in these concentration regions has not been reported until now, the satellite diffuse peaks were observed around the (1 ± δ,0,0) positions at room temperature. The satellite diffuse peaks are explained by a short range atomic concentration wave, which reflects the special shape of the Fermi surfaces in Pt and Pd. The concentration wave is accompanied with the periodic lattice distortions. The lattice spacing at the region with high V concentration shrinks.