APPLICATIONS OF COLLOIDS IN STUDIES OF PHASE-TRANSITIONS AND PATTERNING OF SURFACES

Colloidal dispersions mimic almost all phases of condensed matter and serve as excellent model systems. Therefore, studies of 'model' colloi ds (i.e. particles with tailored surface or geometric properties) unde r equilibrium and nonequilibrium conditions have helped to provide new insights into phase transitions in atomic systems. Moreover, new phas e transitions (such as a homogeneous-->inhomogeneous transition), whic h do not have any atomic analog, have also been discovered. Further, s tructural investigations into charged dispersions in confined geometri es have revealed attraction between similarly charged particles. This attraction appears to be similar to the effective interaction potentia l invoked in the literature in an attempt to explain a number of exper imental results in bulk systems. Studies on ordering of colloids have also led to an interest in taking advantage of self-assembly of colloi dal spheres for fabricating nanostructures and superlattices on solid substrates.