Research

Research overview

Our multidisciplinary research falls under the broad strokes of materials chemistry. Our main interests explore the design, synthesis and physical/structural properties of main group heterocycles. In particular, we are interested in:

Developing new synthetic routes to generate organic radicals and their closed shell precursors.
Design and synthesis of multifunctional, multipurpose organic materials.
Design, crystal engineering and study of complex three-dimensional organic architectures.
Structural studies of low melting point compounds and "soft" materials.
Structural studies of single crystal to single crystal phase transitions.
Design and generation of porous organic materials.
Development of new techniques in X-ray crystallography.
Spin active/light active molecular wires.

Looking for more detail? See below!

Porous Organic Materials

Our porous organic materials objectives are twofold:

Design and use molecular synthons to generate multifunctional porous networks; for example, this may include the incorporation of magnetically active, or light sensitive molecules.
Study the complex interactions that drive self-assembly.

Why are these materials interesting?

There are zero metals in our porous materials (unlike MOFs) and there are zero covalent bonds linking molecules together (unlike COFs) to form a 3D structure. Therefore we are studying the self-assembly of molecular building blocks and their resulting complex multidimensional porous materials.
Understanding the driving forces that yield these structures will help in the design of better, purpose driven materials.
Molecular building blocks are cost effective and easily modified synthetically; they are typically non-toxic and environmentally friendly.

Here's the Spin on Bistability

What is organic radical bistability?

Organic radicals usually have one unpaired electron. This gives rise to a measurable magnetic susceptibility. However, the usual fate of radicals is to pair their spins, forming a covalent bond (or dimer), which "quenches" the magnetic susceptibility.
Sometimes radicals can form dimers and then convert back to radicals via changes in temperature, electric field, light or pressure.
With respect to temperature, most radical/dimer conversions happen at the same temperature. Thus, when you lower the temperature of the material, the radicals within the material form dimers. Then, if you heat the material back up, the dimers convert back to radicals at precisely the same temperature.
In bistable radical systems, there is a temperature region where both radicals and dimers may exist (that is, the thermodynamically stable and metastable forms coexist). We can measure this temperature region using a superconducting quantum interference device (SQUID).

Why are these materials interesting?

In the pursuit of device miniaturisation we can, in theory, use these materials to:

Encode data on single molecules (for example, a 1 or 0).
Act as a molecular switch in molecular-based electronics.

Furthermore, we are interested in the X-ray crystallographic techniques required to study these systems and the underlying physics of the system.

(a) Single crystal X-ray diffraction (SCXRD) model of the high temperature phase, where there are 4 unpaired radicals in the unit cell. The single crystal selected for the experiment is illustrated above. (b) Low temperature SCXRD model showing the dimerisation mode of the radicals. The unit cell has doubled and 4 radicals have dimerised. The remaining 4 molecules are spin active radicals. Note the crystal damage after the phase transition!

Soft Materials

One of our key interests is the study of soft materials and low melting point compounds. For our purposes, we define soft materials as compounds that can be deformed by thermal OR mechanical stress at ambient temperatures. Our approach primarily focusses on systems containing small molecules that self-assemble.

Why are soft materials interesting?

Surfaces can be coated with soft materials.
The use of small molecules allows us to synthetically modify the building blocks.
We can design smart surfaces by incorporating magnetically/thermally/photo active synthons.

Pictured above are SEM images of our latest molecular ribbon. The ribbon is a single crystal that can be bent like a polymer. However, even when bent, the ribbon remains crystalline.

Low Melting Point Compounds

We also investigate low melting point compounds, which are typically defined as liquids at or near room temperature. These systems give us a glimpse of solid-state assembly right at the boundary between liquid and solid phases.

Pictured on the right is an

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