title: Isotropic and nematic liquid crystalline phases of adaptive rotaxanes.
abstract: We describe the thermodynamics of a solution of rotaxanes which can change their length from a short state of length L to a long state of length qL in response to their surrounding environment. We call these rotaxanes "adaptive." We show that such a system can exhibit both isotropic and nematic liquid crystalline phases. The system shows several interesting kinds of behaviour. First we predict that the fraction of short-length rotaxanes increases linearly with concentration and is a maximum at the critical concentration that marks the isotropic to nematic transition. Second, the critical concentration shows a minimum at a certain value of q. Our model suggests that the effect of adaptive length changes is most dramatic at small q and where the long state is slightly favoured.
authors.affiliation: Research School of Chemistry, The Australian National University, Canberra ACT 0200, Australia.
authors.forename: Hao
authors.initials: H
authors.lastname: He
authors.affiliation: Research School of Chemistry, The Australian National University, Canberra ACT 0200, Australia.
authors.forename: Edith M
authors.initials: EM
authors.lastname: Sevick
authors.affiliation: Department of Applied Mathematics, Research School of Physical Sciences and Engineering, The Australian National University, Canberra ACT 0200, Australia.
authors.forename: David R M
authors.initials: DR
authors.lastname: Williams