Abstract
We report an experimental study of the morphological phases of zinc electrodeposits. The microscopic morphology is based on two alternative growth mechanisms: tip splitting or dendritic, and is decoupled from the macroscopic structure. The latter is characterized by the density of branches and stability of the front. The key role in the microscopic selection is played by the initial concentration of zinc. The importance of ion availability is manifested again in the Hecker transition, where the departure from dense branching morphology coincides with the exhaustion of zinc from the original solution. © 1996 The American Physical Society.