Electrochemical Impedance Spectroscopy (EIS) is a sensitive technique for determining the mechanistic pathway of an electrochemical reaction. In particular, the low frequency behavior of the impedance at various over-potentials can help differentiate between very similar mechanisms Nine different mechanisms related to anodic dissolution of metals are simulated and the EIS patterns that are expected for these mechanisms are identified. This library of patterns reported here will help in eliminating certain mechanisms and identifying mechanisms with the least number of parameters that can be applied for modeling experimental EIS data. (C) 2009 Elsevier B.V. All rights reserved.