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

dimerization motif. One possible explanation for the sulfur containing complexes is that
the atomic radius of the sulfur atoms may not be large enough to overcome the steric
hindrance introduced by the bulkiness of the ancillary hfac ligands. The manganese
coordination species II-6, which also contains selenium did not form dimers, but actually
was shown to be isomorphous to the sulfur containing analogue [Mn(hfac) 2 ] 2·pymDTDA
(II-9), reported in a previous communication. 3
b
a
c
Figure 2-7. a) Unit cell of II-6 depicting the ligand disorder and showing the two molecules in the
asymmetric unit. b) Linear propagation of Molecule 2 with ligand shown in head-to-tail orientation.
c) Linear propagation of Molecule 2 with ligand showing head-to-head and tail-to-tail orientations. The
backbone of the ancillary hfac ligands have been removed in all cases for clarity.
The packing of the manganese complexes differs greatly from other binuclear DTDA
and DSDA coordination complexes. There is disorder with respect to the orientation of
79