$Ti ^{2+} \Rightarrow 3 d ^2 4 s ^0$

$t _{2 g } e ^{-}=2$

$e _{ g } e ^{-}=0$

$CFSE =[-0.4 \times 2+0.6 \times 0] \Delta_0$

$-0.8\,\Delta$

(B) ${\left[ V \left( H _2 O \right)_6\right]^{2+}}$

$V ^{2+} \Rightarrow 3 d ^3 4 s ^0$

$t _{2 g } e ^{-}=3$

$e _{ g } e ^{-}=0$

$CFSE =[-0.4 \times 3+0.6 \times 0] \Delta_0$

$-1.2 \Delta_0$

(C) ${\left[ Mn \left( H _2 O \right)_6\right]^{3+}}$

$Mn ^{3+} \Rightarrow 3 d ^4 4 s ^0$

$t _{2 g } e ^{-}=3$

$e _{ g } e ^{-}=1$

$CFSE =[-0.4 \times 3+0.6 \times 1] \Delta_0$

$=-0.6 \Delta_0$

(D) ${\left[ Fe \left( H _2 O \right)_6\right]^{3+}}$

$Fe ^{3+} \Rightarrow 3 d ^5 4 s ^0$

$t _{2 g } e ^{-}=3 \quad e _{ g }=2$

$CFSE =[-0.4 \times 3+0.6 \times 2] \Delta_0$

$=0 \Delta_0$