In this paper we present experiments and simulations on the dissolution of Si into single crystalline Ge(111) substrates The interface shift during the dissolution was tracked by X-ray Photoelectron Spectroscopy It was obtained that the Interface remained sharp and shifted according to anomalous kinetics similarly to our previous measurement in the Si/amorphous-Ge system The interface shift x can be described by a power function of time x proportional to t(kc) with a kinetic exponent k(c) of 0 85 +/- 0 1 larger than the one measured for the amorphous system (0 7 0 1) Both exponents however are different from the k(c) = 0 5 Fickian (parabolic) value and It is interpreted as a nanoscale diffusional anomaly caused by the strong composition dependence of the diffusion coefficients (C) 2010 Elsevier B V All rights reserved