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

propensity for intermolecular Se-N contacts. 15
The distance between DSDA centeroids
defined by the 5 atoms of the DSDA ring was found to be 3.155(11) Å (see Figure 2-4)
and important crystallographic parameters are summarized in table 2-1.
The nickel and two zinc coordination species discussed in this chapter have roughly
octahedral coordination geometry about the metal centers. This is consistent with the
fairly high ligand field stabilization energy that is expected for an octahedral d 8 system
for II-5 and the angles do not deviate from the ideal 90° by more than 3 or 4°.
a
b
c
d
Figure 2-5. ORTEP depictions of the single crystal X-ray structures of a) II-5, b) II-6, c) II-7 and d) II-8
showing 1 molecular unit of each complex demonstrating the local geometry about the metal centers.
Thermal ellipsoids at 50%, F and H atoms have been omitted for clarity.
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