Coherent QENS for the investigation of self-diffusion in intermetallic alloys

Up to now, self-diffusion in intermetallic alloys has been successfully studied in various compounds containing strong incoherent scatterers, namely Ni and Co, by means of QENS. The range of accessible compounds could be significantly enlarged by using coherent scattering. We, therefore, derive the coherent scattering function for self-diffusion via vacancies in intermetallic alloys and consider how coherent scattering can be used for diffusion studies as well as how coherent background in incoherent experiments on intermetallic alloys can be taken into account. (C) 2001 Elsevier Science B.V. All rights reserved.