Exploring the Molecular Growth of Two Gigantic Half-Closed Polyoxometalate Clusters {Mo } and {Mo Ce }.

Understanding the process of the self-assembly of gigantic polyoxometalates and their subsequent molecular growth, by the addition of capping moieties onto the oxo-frameworks, is critical for the development of the designed assembly of complex high-nuclearity cluster species, yet such processes remain far from being understood. Herein we describe the molecular growth from {Mo } and {Mo Ce } to afford two half-closed gigantic molybdenum blue clusters {Mo } (1) and {Mo Ce } (2), respectively. Compound 1 features a hat-shaped structure with the parent wheel-shaped {Mo } being capped by a {Mo } unit on one side. Similarly, 2 exhibits an elliptical lanthanide-doped wheel {Mo Ce } that is sealed by a {Mo } unit on one side. Moreover, the observation of the parent uncapped {Mo } and {Mo Ce } clusters as minor products during the synthesis of 1 and 2 strongly suggests that the molecular growth process can be initialized from {Mo } and {Mo Ce } in solution, respectively.