A Solid-State Supramolecular Rotator Assembled from a Cs-crown Ether Polyoxometalate Hybrid: (Cs⁺)₃([18]crown-6)₃(H⁺)₂[PMo₁₂O₄₀]

A solid-state molecular rotator comprising [18]crown-6 was assembled into a crystalline array of (Cs+)3([18]crown-6)3(H+)2[PMo12O40]5−, whereby two Cs+([18]crown-6) supramolecular rotators were complexed with a two-electron-reduced α-[PMo12O40]5− Keggin cluster. The size-compatible rotators of [18]crown-6 were directly complexed to an α-[PMo12O40]5− axle through Cs+−O interactions. The investigation of the dynamics of the system revealed that two rotation frequencies for [18]crown-6 were observed by using temperature-dependent 1H NMR studies, and these were dominated by intermolecular interactions in the solid state.