Statistical mechanical approach to phase transitions in colloids

Abstract

The Monte Carlo method and a number of approximate theories, based on classical statistical mechanics and using DLVO pair potentials, are used to calculate the structure and the osmotic pressure of electrostatically stabilized dispersions of spherical particles. Reasonable agreement is found between the exact Monte Carlo radial distribution functions and the corresponding quantity determined from the hard sphere model. This hard sphere model provides a simple unifying theory for the structure of these colloidal solutions provided that the equivalent hard sphere diameter is chosen correctly. From the good agreement between experiment and these and previous calculations, we conclude that the DLVO pair potentials are adequate to calculate at least the structure of colloidal solutions.