1,2,3-Dithiazolyl and 1,2,35-Dithiadiazolyl Radicals as Spin-Bearing ...

changes related to geometric, chemical and electronic properties. The incorporation of
metal ions can increase spin and magnetoanisotropy which means that it is important to
design organic radicals which can act as ligands.
Radicals containing sulfur and nitrogen in the heterocyclic components of the spin
bearing rings are of particular interest as they have been shown to exhibit a myriad of
material properties. These properties have been reviewed in previous sections of this
chapter and range from bistability 22 with large hysteresis centered at room temperature,
magnetic behaviour, including ordering and spin-canting, 81 to activated and even metallic
conductivity. 117
The large number of material properties is the primary driving force which has
motivated the selection of thiazyl radials as the focus of this thesis. We endeavor to
design ligands from thiazyl building blocks, thereby creating new paramagnetic ligands
and metal complex architecture, but more importantly the possibility of tapping into the
unique material properties of the thiazyls themselves. The first step is to create new
paramagnetic ligands and test their coordination properties. Then the properties resulting
from intramolecular interactions can be probed. Ultimately intermolecular interactions
(either ligand-ligand interactions or ligand-metal interactions) giving rise to materials
properties are of interest. Ligand and complex design will be adjusted in pursuit of
magnetic, conductive and other bulk material properties and combination of properties. In
particular we introduce molecular components which will improve on our previous
designs by making the radicals more suitable donors for metal ions. In addition we probe
metal-ligand intermolecular contacts is to use the addition of the metal ions to foster
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