Rationalised 2023-24
129
Coordination Compounds
It is usually possible to predict the geometry of a complex from
the knowledge of its
magnetic behaviour on
the basis of the valence
bond theory In the diamagnetic
octahedral 
complex,
[Co(NH3)6]
3+, the cobalt ion
is in +3 oxidation state
and has the electronic
configuration 3d
6 The
hybridisation scheme is as
shown in diagram Orbitals of Co ion
3+
sp d
3
2
3+
hybridised
orbitals of Co
[CoF ]
(outer orbital or
high spin complex)
6
3–
Six pairs of electrons
from six F ions
–
3d
4s
4p
sp d
3
3 hybrid
4d
3d
3d
Six pairs of electrons, one from each NH3 molecule, occupy the six
hybrid orbitals