Since the Co-ordination number of `Mn^(2+)` ion in the complex ion is 4, it will be either tetrahedral (`sp^(3)` hybridisation) or square planar (`dsp^(2)` hybridisation). But the fact that the magnetic moment of the complex ion is 5.9 BM, it should be tetrahedral in shape rather than square planar because of the presence of five unpaired electrons in the d-orbitals.
