Abstract CTS-9806321 Estella Blaisten-Barojas, George Mason University It was observed that an inorganic precipitate (Dogtooth Spar) absorbed at the air-water interface bifurcates into two aggregation structures. One structure develops into a two-dimensional fractal gel previously identified in literature, and another self-organizes into a two-dimensional colloidal periodic structure (lattice) of crystals that was observed for the first time by the P.I. The new crystals have a distorted tetrahedral shape, do not aggregate, and spontaneously may arrange into the periodic structure. The main focus of the project is the clarification of the conditions under which self-organization occurs, characterize the crystals formed at the air-water interface, and understanding the role of crystallites in the respective fractal growth at the air-water interface. The P.I. proposed an initial model that includes the repulsive electrostatic forces and attractive capillary forces. If this model is true, then the observed self-organization could be achieved in other systems. Video microscopy and crystal interaction models will be used in the investigation. If successful, the project will clarify a self-organizing mechanism with relevance to colloidal science and materials synthesis. ***
