 These features can be explained as follows.The ground state of the anion is 2T2g, which derives from the electronic configuration (t2g)5.So, there would be an unpaired electron in the d orbital of Fe3+
From that, the three bands can be assigned to the transitions 2t2g→2t1u1, 2t2g →2t1u2, 2t2g →2t2u.