(c) `d^(1).d^(2)` and `d^(4)` configurations cannot give arise to . Octahedral comolexes, ad octahedral comlexes are formed either by `d^(2)sp^(3)` -hybridisation is presence of strong ligands, called low spin complex as they have compartively less unpaired electrons or by `sp^(3)d^(2-)`-hybridisation (in presence of weak ligands, called high spin complex as they have comparitively more unpaired electrons ) `d^(6)` can give arise to both low spin and hight spin octahedral complexes in presence of strong and weak ligands respectivley.
