November 1, 2007

Technical Expertise

While the intellectual focus of our research lies in structure-property relationships, organic and organometallic synthesis lie near the foundation of all that we do. In general, we synthesize molecules that are well–suited to test specific hypotheses in materials chemistry. The lessons learnt from experimental work are then redirected toward the design and synthesis of new generations of molecules. Current synthetic targets include “mechanophores”–molecules that can be activated mechanically to do new and useful chemistry–and insulators for molecular wires.

We use a combination of the Molecular Force Probe (MFP-3D) developed by Asylum Research and a home-built atomic force microscope to explore the relationship between mechanical forces and chemical activation. This technique has provided new insights into: (1) the dynamics of self-repair in reversible polymer interfaces; (2) the mechanical activation of ligand exchange in coordination complexes; and, (3) the mechanical activation of electrocyclic rearrangements along a polymer backbone.

We are fortunate to having ongoing collaborations with the laboratories of Prof. Piotr Marszalek, Prof. Boris Akhremitchev, and Prof. Rob Clark, experts in force microscopy.

One of the most reliable ways to characterize the structure of assembled aggregates in solution is through a combination of static and dynamic light scattering. We employ both techniques extensively, either in batch mode or as a detector coupled to a size exclusion or other chromatography column. We use a Wyatt DAWN and QELS system, and a combination of the two techniques, when accessible, is especially informative.

We currently use a wide range of techniques including rheometry, size exclusion chromatography, contact angle measurements, ellipsometry, AFM imaging, X-ray diffraction, multi-dimensional NMR, MALDI-TOF, flourescence spectroscopy, XPS, SEM, and TEM. These techniques are available either in our lab or in central facilities.  Oh, and sometimes we do chemistry by hitting things with hammers:

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