title: Designed patterns: flexible control of precipitation through electric currents.
abstract: Understanding and controlling precipitation patterns formed in reaction-diffusion processes is of fundamental importance with high potential for technical applications. Here we present a theory showing that precipitation resulting from reactions among charged agents can be controlled by an appropriately designed, time-dependent electric current. Examples of current dynamics yielding periodic bands of prescribed wavelength, as well as more complicated structures are given. The pattern control is demonstrated experimentally using the reaction-diffusion process 2AgNO3 + K2Cr2O7-->under Ag2Cr2O7 + 2KNO3.
authors.affiliation: Theoretical Physics Department, University of Geneva, CH-1211 Geneva 4, Switzerland.
authors.forename: I
authors.initials: I
authors.lastname: Bena
authors.forename: M
authors.initials: M
authors.lastname: Droz
authors.forename: I
authors.initials: I
authors.lastname: Lagzi
authors.forename: K
authors.initials: K
authors.lastname: Martens
authors.forename: Z
authors.initials: Z
authors.lastname: Rácz
authors.forename: A
authors.initials: A
authors.lastname: Volford