Monday, 28 November 4:00pm – 5:00pm

This seminar will be delivered in Chemistry Lecture Theatre 4 and Online Zoom. Please email chemistry.researchsupport@sydney.edu.au for zoom link and password.

Speaker: Ms Zixi Xie; University of Sydney

Supervisor: Prof. Cameron Kepert

Title: Controlling anomalous structural properties and spin transition behaviours in stimuli-responsive metal-organic frameworks

Abstract: There is burgeoning interest in designing stimuli-responsive metal-organic frameworks (SR-MOFs). For example, tuning the properties of a SR-MOF in the presence of stimuli enables their promising applications in sensing, molecular machines, information devices and artificial muscles. MOF materials exhibiting spin crossover (SCO) behaviours are one subset of SR-MOFs. A key challenge is the design of materials with controllable properties and distinct behaviours under different stimuli. Understanding the interplay between external stimuli, intrinsic structure and spin state properties is significant for creating desirable materials.

This PhD research involves the synthesis, characterisation and analysis of the properties of SR-MOFs. This seminar will detail the influences of temperature, pressure and guest molecules as stimuli to the SR-MOF materials. Mixed pillaring ligands and cynometallate linkers approaches were investigated to produce tunable structural properties and SCO behaviours. Anomalous lattice motions of negative thermal expansion (NTE) and negative linear compressibility (NLC) induced by temperature and pressure, respectively, were demonstrated. The insight of these SR-MOFs elucidates the interplay between the various stimuli, reversible spin state transition and structural distortions. This work paves the way towards the rational design of controllable ‘smart’ materials.