The calculated values of ligand field splitting energy (10Dq), the
Racah interelectronic repulsion parameter (B), the nephelauxetic
ratio (b), and the ratio m2/m1 (Table 4) support the proposed geometry
for all the synthesized Ni(II) and Co(II) octahedral complexes.
The nephelauxetic ratio (b) for the Co(II) and Ni(II) complexes is
less than one suggesting partial covalency in the metal ligand
bond. The octahedral geometry of these complexes is further supported
by the value of m2/m1. In general, sterically bulky ligands give
rise to relatively low Dq values [21]. Here, the value of 10Dq obtained
in the case of 3-((1H-indol-3-yl)methylene)pentane-2,4-
dione (L2) metal complex is relatively low which clearly show
the considerable amount of bulkiness in the complex.