Charged colloids exhibit a variety of order-disorder and structural transitions. If the interactions can be treated in a Debye-Hückel approximation and if the dielectric constant of the solvent arises from free dipoles and follows a Curie law, the partition function is temperature independent and the system is athermal. If the dielectric constant of the solvent increases faster than linearly with inverse temperature (as is the case for H2O) then the high-entropy phase occurs upon either heating or cooling from the more-ordered phase. As an illustration of these effects the FCC-BCC transition of colloidal crystals as a function of density and screening length is calculated.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films
- Colloid and Surface Chemistry