Tracer correlation, collective correlation and vacancy wind factors in intermetallics taking the B2 structure

In this paper we review the present state of knowledge on diffusion correla tion effects in intermetallic compounds which adopt the B2 structure. We ha ve put emphasis on recent findings. We analyse the behaviour of the tracer correlation factors for both the generalized vacancy and the six-jump-cycle mechanisms and their inter-relationship. We discuss the correlation factor s contained in the isotope effect experiment. We review findings of the beh aviour of the collective correlation Factors and vacancy wind factors. We d iscuss the predictions of Manning's formalism for the vacancy wind factors and what is predicted from the six-jump-cycle mechanism.