Scientists have discovered that when the iron oxide, Fe4O5, is cooled to temperatures below 150K, it goes through an unusual phase transition related to a formation of charge-density waves - which lead to a "four-dimensional" crystal structure.

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Scientists have discovered that when the iron oxide, Fe4O5, is cooled to temperatures below 150K, it goes through an unusual phase transition related to a formation of charge-density waves - which lead to a "four-dimensional" crystal structure.