The permanganate ion () is renowned for its intense purple colour. Given that the central Manganese — d and f Block Elements Chemistry Question

💡 Solution & Explanation

Because Manganese is in the $+7$ oxidation state ($3d^0$), there are absolutely no $d$ -electrons available to undergo standard $d-d$ transitions. The intense purple colour is exclusively due to Charge Transfer Spectra, specifically LMCT. Visible light provides the energy to temporarily excite an electron from the completely filled $p$ -orbitals of the $O^{2-}$ ligands into the vacant $d$ -orbitals of the highly charged $Mn^{7+}$ center.