Enss V., Weder R. Inverse two cluster scattering (35K, LaTeX 2.09) ABSTRACT. We prove that the effective potential for the interaction between two clusters of quantum mechanical particles is uniquely determined by the high velocity limit of any one of the modified Dollard scattering operators. We give a formula with error term for the reconstruction of the effective potential which may be of long range. Available through http://www.iram.rwth-aachen.de/~enss/ or anonymous ftp from work1.iram.rwth-aachen.de (134.130.161.65) in the directory /pub/papers/enss/ as en-95-2.tex, dvi, ps