What is the ground state of solid hydrogen?

The Journal of Chemical Physics website has a fascinating podcast with Roald Hoffmann, Neil Ashcroft, and Vanessa Labet talking about a series of 4 papers they have just published about "molecular" hydrogen under pressure. They illustrate some very rich and subtle physics and chemistry.

It highlights the importance of both physical and chemical insight, simple models, and how there are still these old problems waiting to be solved.

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