Daily answer writing · Sun, 18 Oct, 2026
Why is [Co(NH₃)₆]³⁺ diamagnetic but [CoF₆]³⁻ paramagnetic? CFSE of both
$\ce{[Co(NH3)6]^3+}$ is diamagnetic while $\ce{[CoF6]^3-}$ is paramagnetic. Explain on the basis of crystal field theory. Calculate the crystal field stabilisation energy (in terms of $\Delta_o$ and $P$) and the spin-only magnetic moment of each complex.
Syllabus: Common to CSE Paper I, IFoS Paper I and Geo-Scientist Mains (inorganic): crystal field theory, magnetic properties of complexes.
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