Xenon reacts with ice!

OK, xenon won’t be react­ing with the ice in your freezer. But appar­ently, if you ramp up the tem­per­at­ure and pres­sure enough, then it reacts to form a crys­tal­line com­pound with unit cell con­tain­ing Xe4O12H12. Suit­able con­di­tions for this occur inside plan­ets like Uranus and Neptune.

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