where $\varepsilon_{\mathrm{a}} \Rightarrow$ absorbed energy (splitting energy)

$\lambda_{\mathrm{a}} \Rightarrow$ absorbed wavelength

Presence of $\mathrm{SFL} \Rightarrow \varepsilon_{\mathrm{a}}(\uparrow) \lambda_{\mathrm{a}}(\downarrow)$

$\mathrm{H}_{2} \mathrm{O}<\mathrm{NH}_{3}<$ en ligand strength $\uparrow$ splitting energy $\uparrow$ so absorbed $\lambda \downarrow$