The synthesis behaviour and characterisation of nanocrystalline materials is presented. The materials synthesised are ZnO and InP doped with shallow donors and acceptors, respectively. Characterisation was performed with radioactive isotopes using the perturbed γγ angular correlation technique (PAC), thereby yielding local information on an atomic scale. The characterisation was supplemented by X-ray diffraction, transmission electron microscopy, UV/VIS absorption spectroscopy, photoluminescence spectroscopy, and extended X-ray absorption fine structure spectroscopy. It was shown that the successful incorporation of dopants in nanocrystalline ZnO and InP requires annealing at temperatures at which the growth of the nanocrystals in the sample becomes a significant process.