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Not AvailableAmphidynamic crystals are a type of condensed matter that blends two extremes of the dynamic spectrum: rigid components forming a static lattice and rapidly moving parts. Among them, ordered rotor arrays within metal-organic frameworks (MOFs) constitute a promising platform to explore unchartered territories, such as gas phase-like dynamics in the crystalline state. Through quantum mechanical (QM) calculations and molecular dynamics (MD) simulations we verified that nearly barrierless cubane rotators in CUB-5 display rotational dynamics that transitions from continuous or inertial at high tempera-ture, to chaotic behavior, and ultimately to discrete jumps, as the temperature decreases from room temperature down to cry-ogenic conditions. 1H NMR spin-lattice (T1) relaxation measurements corroborate our theoretical predictions, with experi-mental rotational activation energy of 0.17 kcal/mol and an attempt frequency of 1.03×1012 s-1 that compare well with calcu-lated values of 0.15 kcal/mol and 0.38×1012 s-1, respectively.