Coordination Compounds Part 2

The given complexes are:
[Ti(H2O)6]3+,[Co(H2O)6]2+,[Co(CN)6]−3,[Cu(NH3)4]2+
CN−is the strongest ligand among the given complexes CFSE value for the [Co(CN)6]−3 complex will be highest as it has d6 configuration with a CFSE value of −2.40∆0+2P, where P represents pairing energy and ∆0 represents splitting energy in octahedral field.
The value of ∆0 is high for cyanide complexes.