Table 1:

Hammett parameters of the ligand substituents and selected spectral parameters for complexes 1-4.

Compound	Hammett parameter (σ−)	λ (nm, eV)	ε (M−1 cm−1)
1	−0.13	412, 3.00	2426
2	0.0	415, 2.99	2288
3	0.65	457, 2.71	1502
4	1.27	510, 2.43	228