Template-induced crystal growth

The process of "mineralisation" in biology leads to a diversity of inorganic structures based on silica or calcium carbonate. Some of these are composite and, at the same time, highly crystalline. In all cases a molecular or self assembled "template" species has been identified as the promoter for the crystallisation of the new structure. In biology these "templates" are the end step in the conveyance of genetic information to the inorganic synthesis and an understanding of how they work is the key to mimicking biomineralisation in the laboratory. The lecture will describe how modern scattering methods, using x-rays and neutrons, have revealed the very first steps in the process from the first association of the inorganic with the "template" in zeolite and mesoporous silicate syntheses in the bulk and at interfaces. We now have some control of the phase diagram at surfactant interfaces and novel nanoscale structures have been produced and quantitative thermodynamic information on the kinetics of growth between 20Å and 1000Å will be discussed. It now seems to be possible also to reproducibly create structure at the micron scale and the lecture will describe some of these developments.