Liesegang bands

N. Curtis, D. G. Leaist. Interdiffusion of aqueous silver nitrate and potassium chromate and the periodic precipitation of silver chromate Liesegang bands. Ber Bunsen-Ges—Phys Chem, Chem Phys 702 164, 1998. 

Ortoleva, P. (1984). The self-organization of Liesegang Bands and other precipitate patterns. In Chemical Instabilities Applications in Chemistry, Engineering, Geology and Material Science, ed. G. Nicolis F. Baras, pp. 289-97. Dordrecht Reidel. 

Fu, L., Milliken, K.L., Sharp Jr., J.M. (1994). Porosity and permeability variations in fractured and Liesegang-banded Breathitt sandstones (Middle Pennsylvanian), eastern Kentucky Diagenetic controls and implications for modeling dual porosity systems. Journal of Hydrology, 154, 351-381. 

P. Ortoleva "The Self Organization of Liesegang Bands and Other Precipitate... 

Model of Liesegang Banding," J. Stat. Phys. (submitted for publication). 

THE SELF ORGANIZATION OF LIESEGANG BANDS AND OTHER PRECIPITATE PATTERNS... 

Precipitation/dissolution kinetics coupled to transport can lead to a number of interesting pattern forming processes, the most well studied being the Liesegang bands. Here we review these phenomena and a number of models that have been set forth to explain them. Geological applications of the theory will be discussed. 

In the century of research on Liesegang banding and other precipitate patterning phenomena, many effect have been noted [l-5l A partial list is as follows. 

The model is essentially that of Ostwald which emphasized a cycle of supersaturation, nucleation and depletion of co-precipi-tates to explain Liesegang bands [9] However this theory, especially as formulated mathematically by Prager [10] emphasizes the presence of a gap between bands. This occurs in the model presented here as a special limit of parameter values but is not required. The model presented here as well as teh Ostwald-Prager theory are designed with phenomenon (i) in mind. They clearly cannot explain the other phenomena, however. 

Strickholm, P. and Ortoleva, P., Particle Size Distribution Effects in the CPG Model of Liesegang Banding, J. Chem. Phys. (submitted for publication) ... 

Both cases, svegliabile and cognitc, are observed in our theory of metamorphic layering and stylolization to be presented here. Liesegang banding is discussed in the other article by the the author in these proceedings. 

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