I need to draw a simple crystal field splitting diagram and identify the lowest-energy spin-allowed ligand field band in the electronic absorption spectrum for [MnCl6]2-. I know the basics of the crystal field theory splitting and how to differentiate between the strong field ligands and the weak field ligands, but I am unsure how to place the electrons into the orbitals. Could someone please explain to me how to complete this problem (not necessarily with this complex).
There are two possible ways to fill the orbitals, which result in either a high spin or a low spin complex. In a high spin complex, the orbitals are filled according to Hundt's rule, and a configuration with the maximum number of unpaired spins is obtained. In a low spin complex, the orbitals lower in energy are filled first with as many electrons as possible, resulting in a configuration with more double-filled orbitals. Whether a low spin or high spin complex is formed depends on the strength of ligand field splitting. Weak ligands form high spin complexes, while strong ligands can favor the low spin configuration.