Florin D. Buzatu

An exactly solvable model for a ternary solution with three-body interactions and orientationally dependent bonding.

A model is considered in which the bonds of a honeycomb lattice are covered by rodlike molecules of types AA, BB, and AB. Neighboring molecular ends have three-body and orientation-dependent interactions. The model is shown to be equivalent to a spin-1/2 Ising model on the same lattice with a field, but with only pairwise interactions. Symmetric and asymmetric coexistence surfaces for the separation into an AA-rich and a BB-rich phase are calculated exactly.

Spinodal Curve of a Model Ternary Solution

We consider a lattice model for ternary solutions in which the lattice bonds are covered by molecules of types AA, BB, and AB, and the only interactions are between the molecular ends of a common lattice site. Using its equivalence with the standard Ising model for magnets, we derive the spinodal curve of the three-component model on the honeycomb lattice in the mean-field and Bethe-lattice approximations. The spinodal and the coexistence curves of the ternary solution are drawn at different values of the reduced temperature, the only parameter of the model. The particular case of a binary solution is also illustrated.

Amphiphile-rich phase in a model ternary solution on the honeycomb lattice

A model three-component system is considered in which the bonds of a honeycomb lattice are covered by bifunctional molecules of types AA, BB, and AB. The AB type molecule represents an amphiphile. An accurate approximation to the boundary in temperature-composition space of an ordered amphiphile-rich phase is calculated by transforming an accurate closed-form approximation of the critical frontier of an antiferromagnetic phase in an equivalent Ising model. This Ising model has coupling constants and a magnetic field that are temperature dependent.