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* In 1986, I was asked to review the chemical synthesis of F₂ in Paris at the 100^th anniversary of the discovery of fluorine by Moissan.

* One week before the congress, while preparing my slides, I realized from my work on the fluorine gas generators that there is no reason why F₂ should not be preparable by chemical means. The combination of two rudimentary principles should afford F₂:
- Anions are weaker oxidizers that their neutral parent compounds and these, in turn, are weaker oxidizers than the corresponding cations.
- Stronger acids displace weaker acids from their salts.

* I also knew that MnF₆^2- can be prepared in an aqueous medium:
2KMnO₄ + 2KF + 10 HF + 3H₂O₂ = K₂MnF₆ + 8H₂O + 3O₂
and that MnF₄ is thermodynamically unstable and decomposes at room temp to a lower fluoride and F₂:
MnF₄ = MnF₃ + 1/2F₂
So I raced to the lab, prepared K₂MnF₆ from aqueous HF, ran a displacement reaction with SbF₅:
K₂MnF₆ + 2SbF₅ = 2KSbF₆ + MnF₃ + 1/2F₂
and in 3 days I had successfully prepared elemental fluorine by chemical means in high yield and at atmospheric pressure. The rest is history. The only irony was that both K₂MnF₆ and SbF₅ had been known for more than 100 years and even Moissan could have come up with this scheme, had he thought of it.