Friday, 17 June 11:00am – 12:00pm

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: Miss Eleanor Kearns; The University of Sydney

Supervisor: Prof. Deanna D’Alessandro

Title: Elucidation of Structure Activity Relationships in TTF-based Metal-Organic Frameworks (MOFs)

Abstract: Metal–organic frameworks (MOFs) are crystalline and periodic 3D structures which provide an ideal platform for probing structure-activity relationships (SARs) in the solid state. This work builds on the unique multifunctional behaviour recently discovered in a tetrathiafulvalene (TTF) based MOF which undergoes a reversible single-crystal-to-single-crystal (SC-SC) double [2+2] photocyclisation (Figure 1).¹ Herein,  a family of photoactive TTF-based MOFs were generated by the systematic variation of the framework constituents. This modular building block approach was then used to probe the effect of structure on the intervalence charge transfer (IVCT) and [2+2] photocyclisation inherent to these materials using a combination of analytical techniques including spectroscopy, electrochemistry, and X-ray crystallography. The Johnson-Mehl-Avrami-Kolmogorov and Finke-Watzky kinetics solid-state models have been applied to the photocyclisation reaction and an interesting temperature dependence found. This work represents one of the first in-depth kinetic analyses in MOFs. Understanding the SARs associated with these complex fundamental processes in MOFs is critical towards their eventual deployment as multi-stimuli responsive “smart” materials with real world ramifications.

Figure 1: The double [2+2] photocyclisation observed in the parent framework (top). Effect of ligand substitution on the framework topology (bottom).

References

1             D. A. Sherman, R. Murase, S. G. Duyker, Q. Gu, W. Lewis, T. Lu, Y. Liu and D. M. D’Alessandro, Nat. Commun., 2020, 11, 2808.