With funding from the Organic Dynamics Program of the Chemistry Division, Professors Sanford Asher, Rob Coalson, and Anthony Duncan will conduct theoretical and experimental studies leading to an understanding of electrostatic interactions in strongly interacting colloidal dispersions. The project will explore the possibility of exploiting these interactions to produce novel colloidal crystalline materials. In part the work will study colloidal crystals composed of mixed positive and negative colloidal particles. The primary techniques to be employed are photothermal diffraction spectroscopy, fluorescence bleaching, molecular dynamics simulations, and other theoretical treatments. The weaknesses in DLVO (Derjaguin-Landau-Verwey-Overbeek) theory, applicable to weakly interacting colloidal systems but substantially flawed when interactions are strong and particle densities high, are expected to be overcome by a new lattice field theory (LFT) approach. The crystalline colloidal arrays represent an unusual arrangement of matter and are of importance to material science. The work deals with interfacial chemistry of large charged colloidal particles and with the consequent electrostatic potentials and electric fields. Electrostatics are crucially important in membrane biology. Models developed for colloidal particles at high density, although not necessarily directly applicable, may thus also have biological relevance.
