The Interaction between Soft Interfaces: Forces and Structural Aspects

Soft interfaces constituted by two‐dimensional molecular layers play important roles in numerous technological applications and are major components of all biological matter, for example in the form of biomembranes. The mutual interaction between such interfaces often crucially influences their function as well as the structural organization of the entities they form. The forces acting between two soft interfaces in liquids not only depend on their chemical properties, like charge density or hydrophilicity. They are often also closely connected to the structural response of the interfaces to their interaction, for instance in terms of molecular conformations or ion distributions. This interplay renders the description of the interaction between soft or chemically complex interfaces challenging. In the present article, various experimental and theoretical approaches to the study of interacting soft interfaces are reviewed with a focus on structural aspects.