What is the CFSE for [FeF6]3- ?

0 Dq -12 Dq 24 Dq 20 Dq

0 Dq

In [FeF6]3-  x + 6(-1) = -3 x - 6 = -3 x = -3 + 6 = 3 26Fe : [Ar]4s23d6 Fe3+ : [Ar]3d5 Since F− is a  weak ligand according to CFSE theory there will be 3 electrons in three t2g​ orbital and 2 electrons in two eg​ level. So, CFSE = (-4 x 3)Dq + (+6 x 2)Dq = 0