title: Broken symmetry and the variation of critical properties in the phase behaviour of supramolecular rhombus tilings.
abstract: The tiling of surfaces has long attracted the attention of scientists, not only because it is intriguing intrinsically, but also as a way to control the properties of surfaces. However, although random tiling networks are studied increasingly, their degree of randomness (or partial order) has remained notoriously difficult to control, in common with other supramolecular systems. Here we show that the random organization of a two-dimensional supramolecular array of isophthalate tetracarboxylic acids varies with subtle chemical changes in the system. We quantify this variation using an order parameter and reveal a phase behaviour that is consistent with long-standing theoretical studies on random tiling. The balance between order and randomness is driven by small differences in intermolecular interaction energies, which can be related by numerical simulations to the experimentally measured order parameter. Significant variations occur with very small energy differences, which highlights the delicate balance between entropic and energetic effects in complex self-assembly processes.
authors.affiliation: School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, UK. andrew.stannard@nottingham.ac.uk
authors.forename: Andrew
authors.initials: A
authors.lastname: Stannard
authors.forename: James C
authors.initials: JC
authors.lastname: Russell
authors.forename: Matthew O
authors.initials: MO
authors.lastname: Blunt
authors.forename: Christos
authors.initials: C
authors.lastname: Salesiotis
authors.forename: María del Carmen
authors.initials: Mdel C
authors.lastname: Giménez-López
authors.forename: Nassiba
authors.initials: N
authors.lastname: Taleb
authors.forename: Martin
authors.initials: M
authors.lastname: Schröder
authors.forename: Neil R
authors.initials: NR
authors.lastname: Champness
authors.forename: Juan P
authors.initials: JP
authors.lastname: Garrahan
authors.forename: Peter H
authors.initials: PH
authors.lastname: Beton
mesh_terms: D008962:Models, Theoretical; D013499:Surface Properties