Metastability by design: new paradigms for functional molecular materials

Description

The design and development of responsive “smart” materials is a key challenge in contemporary materials science, with applications ranging from chemical sensing and environmental monitoring to personal medicine and fashion. Selectively trapping long-lived metastable states provides a new and relatively unexplored, but highly-promising, route to materials with selective responses to a range of environmental stimuli.

In this talk, I will discuss three examples. Square-planar Pt complexes based on tridentate “pincer” ligands produce needle-like crystals where the Pt-Pt stacking and colour can be perturbed by diffusion of small molecules through the crystallites, and the solvent selectivity and response controlled via the ligand chemistry. Solid-state linkage isomers show a photoinduced change in ligand binding through a single-crystal-to-single-crystal phase transition. Using time-resolved single-crystal X-ray diffraction and kinetic modelling, I will show how the metastable-state lifetimes can be tuned through orders of magnitude by varying the temperature. Finally, I will also present a family of thermochromic organic cocrystals that show a series of temperature-induced SCSC transitions, enabled by molecular disorder introduced with a novel crystal-engineering strategy.

Finally, I will also highlight how a combination of spectroscopy, crystallography and modelling can together yield the atomistic understanding needed to exploit metastability as a design strategy in the future.

Period	17 Sept 2018
Event title	European Materials Research Society (EMRS) Fall Meeting 2018
Event type	Conference
Location	Warsaw, PolandShow on map
Degree of Recognition	International