[yeders]

Hi.

As Mn(II) has a d5 electron config, what are the possible ground states for a d5 ion?
and why are Mn(II) complexs normally pale?
and why is the permanganate ion MnO4^- very dark violet in colour??

cheers guys

[vladi307]

You must draw the 5 d orbitals according the theory of crystallic field. If you move an electron then you have change of the spin number. This is not permissible. Since you don't have an electron jump you don't expect  colour in Mn(II) substances. Mn (7+) haven't d electron but accept an electron from oxo-ligands in the MnO4. This is an electron transfer and because the electron gap is inside the visible spectra you see the dark violet colour. This is a small reduction of Mn that accepted electron from the oxygen. You can see that if you draw the orbitals of metal and of the ligands according  the theory of molecular orbitals.