Interactions of iron implants in transition metals

Abstract

Au, Ir, Pt, Rh, Ti, and W foils were implanted with $^{57}\mathrm{Fe}$ ions with doses from ${10}^{15}$ to 5\ifmmode\times\else\texttimes\fi{}${10}^{16}$ ions/${\mathrm{cm}}^{2}$ and studied at room temperature by conversion electron M\"ossbauer spectroscopy. It has been proved that the macroscopic heat of solution of Fe in respective metals is a primary parameter determining the state of implanted specimens. For an attractive Fe-Fe potential the iron implants are observed in the form of aggregates, while for a repulsive Fe-Fe potential, they are not distinguishable in M\"ossbauer spectra. Molecular-dynamics simulations showed that the final arrangement of atoms within a thermal spike is maintained during about 1.2 ps.