Umakant biswal
Last Activity: 7 Years ago
dear yuvraj
The color in KMnO4 arises from an electronic transition, but it is actually not a d-d transition, since the Mn in this compound has no d electrons.
it arises from a charge transfer reaction within a molecule , in which photon promote an electron from the highest energy molecular orbital in one of the Mn-o bond to an empty d orbital on the manganese ,
the promotion in equivalent to the energy of a yellow photon
so, yellow light is absorbed leaving us to see its purple colour .
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