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

(derived from angles ranging from 47.01(11) to 66.2(9)°). However there are several
exceptions where the phenyl substituent lies almost perpendicular to the equatorial plane
(86.6(9)°) or almost parallel to the equatorial plane (6.51(11), 10.9(7) and 13.3(7)°). A
full list of these angles and their corresponding polymorph is given in table 4-2. The
angles which are close to 0° or 90° are in bold.
IV-2a
PCSTIB04
IV-2b
PCSTIB02
IV-2c
PCSTIB01
IV-2d
PCSTIB03
Sb1 39.68(11) 40.0(4) 34.3(9) 52.3(6)
47.01(11) 33.1(4) 54.7(9) 13.3(6)
49.01(11) 60.0(4) 86.6(9) 26.6(6)
Sb2 24.96(11) 66.2(9) 52.4()
6.51(11) 51.2(9) 54.6(6)
51.40(11) 32.0(9) 38.1(6)
Sb3 52.4(6)
66.0(6)
41.4(6)
Sb4 59.5(6)
10.9(6)
37.9(6)
Table 4-2. Twist angle of phenyl ring (defined by six carbon atoms of each phenyl ring) with respect to the
equatorial plane of the molecule (defined by the antimony and the three coordinated carbon atoms).
Another interesting structural feature which indicates the extent to which these
molecules are strained is the angle created between the central antimony atom, the
coordinated carbon atom and the carbon atom in the para position of the same phenyl
ring. These angles do not differ substantially from the expected 180° however and range
from 174.9(3) to 179.9(4)°.
The thermodynamically preferred polymorph IV-2b has the simplest packing motif
and contains only one molecule in the asymmetric unit. The three phenyl rings about the
antimony center are arranged in a propeller-like fashion with each of the mean planes of
the phenyl rings rotated in the same direction with respect to the trigonal plane of the
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