Magnetic moment of K3[CoF6]
- The magnetic moment of the complex K3[CoF6] is 5.0 B.

Stabilization energy
- The stabilization energy is the energy released during the formation of a complex from its constituent ions.
- The greater the stabilization energy, the more stable the complex.
- The stabilization energy can be calculated using the crystal field theory.

Crystal field theory
- According to the crystal field theory, the metal ion in a complex is surrounded by a set of negatively charged ligands.
- The ligands repel the electrons in the metal ion, causing the energy levels to split.
- The magnitude of the splitting depends on the nature of the ligands and the geometry of the complex.
- The energy difference between the highest and lowest energy levels determines the magnetic properties of the complex.
- The magnetic moment of the complex is related to the number of unpaired electrons in the highest energy level.

Calculation of stabilization energy
- The stabilization energy can be calculated using the following equation:
ΔE = -0.4Bn(unpaired)
where ΔE is the stabilization energy, B is the crystal field splitting energy, n is the number of ligands, and unpaired is the number of unpaired electrons in the highest energy level.
- In this case, the complex has a magnetic moment of 5.0 B, which indicates the presence of one unpaired electron in the highest energy level.
- Therefore, unpaired = 1 and n = 6 (since there are six ligands in the complex).
- The crystal field splitting energy for octahedral complexes with strong field ligands is 0.4 Δo, where Δo is the crystal field splitting parameter.
- For Co(III), Δo is approximately 10,000 cm-1.
- Therefore, B = 0.4 x 10,000 = 4000 cm-1.
- Substituting these values into the equation, we get:
ΔE = -0.4 x 4000 x 1 x 6 = -9600 cm-1 = -0.96 eV.

Conclusion
- The total stabilization energy of the complex K3[CoF6] is -0.96 eV or -9600 cm-1.
- The correct answer is option 'A'.