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

well as discuss the experiments that were carried out to determine the nature of the other
polymorphs and the conditions under which they can be formed.
4.2 X-ray Crystallography
The new polymorph of IV-2 (IV-2a) was found to exist in the space group Pc. Data
were collected at 150 K and later at room temperature to confirm that it was not a low
temperature phase of IV-2. This also allows a direct comparison to the other polymorphs
which were analyzed at room temperature. There are two crystallographically unique
IV-2
Figure 4-1. ORTEP depiction of the asymmetric unit of IV-2a showing both
crystalographically unique molecules. 50% probability ellipsoids, H atoms omitted
for clarity.
molecules in the asymmetric unit, as can be seen in Figure 4-1. The antimony complex
was shown to possess trigonal bipyramidal geometry about the antimony center with the
chlorine atoms occupying axial positions and the phenyl substituents occupying the
equatorial sites in agreement with Bent’s Rules.
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