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

a
b
c d e
Figure 1-16. a) Nonorthogonal overlap of d xz and p z orbitals, b) Orthogonal overlap of d yz and p z orbitals,
c) Orthogonal overlap of d xy and p z orbitals, d) Orthogonal overlap of d z 2 and p z orbitals, e) Orthogonal
overlap of d x
2
-y 2 and p z orbitals.
The other portions of Figure 1-16 show potential interactions that can take place with
the other t 2g orbitals and the e g set of d-orbitals. Figure 1-16c shows the p z and d xy
orbitals, d shows the p z orbital and the d 2 2
z orbital and e shows the d 2 x -y and the p z
orbitals. In each of these cases the amount of constructive and destructive interference are
equal, resulting in an overlap integral of zero. This is referred to as orthogonal overlap
and Hund’s Rule of Maximum Multiplicity states that for two electrons in orthogonal,
adjacent orbitals, the lowest energy state is one that maximizes the multiplicity.
Therefore the electrons must have the same value of m s . These interactions are related to
the concepts of antiferromagnetic (as in the case of the former) and ferromagnetic (as in
the case of the latter) that we have examined already and will dictate the magnetic
properties that are of interest in the systems that will be examined.
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