The size distribution of Pb inclusions formed by high-dose ion implantation in crystalline Si has been studied with a variety of experimental techniques. Results obtained from small angle x-ray scattering, transmission electron microscopy, and low-temperature magnetic moment measurements are compared. For samples implanted at room temperature, the results depend on which technique has been used, due to the amorphization of the silicon. The experiments on the samples implanted at an elevated temperature yield compatible results.

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We induced Co to form inclusions in Ag by ion implantation of Co into Ag and by coevaporation of both elements in a MBE system. Mössbauer spectroscopy at 4.2 K reveals the hyperfine fields present in the bulk and at the interface of the precipitates. By post-implanting the 57Co activity into the coevaporated samples, we strongly enhanced this interface population, which facilitates the determination of the associated magnetic hyperfine field. The dependence of the precipitate size on the Co concentration and annealing treatment is monitored. We propose a simple model which allows to estimate the precipitate size in the case of preferential interface population.

An analysis of the pressure dependence of the Griineisen parameter y and the Debye temperature 8 for CsI based on the model developed by Kumari and Dass is presented. From the pressure dependence of the recoilless fraction behaviour y is deduced which shows that y varies linearly with pressure as y ( p , T ) = yoyp, where q is found to be pressure independent. 8 ( p ) also displays a linear variation with p , which is consistent with the recoilless fraction behaviour of y-ray emission or absorption in the Mossbauer effect for low pressures. Various thermodynamic approximations implied in the analysis are tested and found to be true.

In the present study we aim to investigate the onset of Co cluster formation in Ag by Mössbauer spectroscopy. Hyperfine interaction techniques are very powerful in determining the onset of formation of very small clusters because they probe the atomic environment present at the radioactive probe atom's site. We employed different sample preparation techniques and discuss the differences between them. We could establish the proper conditions for obtaining a large fraction of Co dimers. The behaviour of the different components in the Mössbauer spectra as a function of the Co concentration allows us to estimate the typical trapping radius for Co dimer formation.