Thus, the complex has octahedral geometry and is
diamagnetic because of the absence of unpaired electron In the formation
of this complex, since the inner d orbital (3d) is used in hybridisation,
the complex, [Co(NH3)6]
3+ is called an inner orbital or low spin or spin
paired complex The paramagnetic octahedral complex, [CoF6]
3– uses
outer orbital (4d ) in hybridisation (sp
3d
2) It is thus called outer orbital
or high spin or spin free complex