Modulated phases and structural arrest in colloidal systems with competing interactions

Abstract

We review some recent results relevant to colloidal systems with competing interactions. In particular we report some findings concerning the pattern formation phenomena obtained in a φ⁴ theory. Some of the general features are also found in an atomistic model by means of a thermodynamic approach and molecular dynamics simulations. Finally this model is shown to exhibit a structural arrest in a disordered gel-like state, once the ordered state is avoided.

Keywords:

• colloids
• competing interactions
• pattern formation
• columnar and lamellar phases
• dynamical arrest

Acknowledgments

This paper is dedicated to Luciano Reatto on the occasion of his 70th birthday, who has contributed much to the subject of this paper. We would like to thank our collaborators, E. Del Gado, M. Tarzia and N. Sator, on these topics. This work is partially supported by Italian SuperComputing Resource Allocation – ISCRA.

Notes

Note

1. The potential used in 23 was actually formally different,

where , and . The two potentials Equations (2) and (3) are however practically indistinguishable, also considering that both are truncated at long distances.