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Supramolecular nanocages with inner cavities have attracted increasing attention due to their fascinating molecular aesthetics and vast number of potential applications. Even though a wide array of discrete supramolecular cages with precisely designed sizes and shapes have been established, the controlled assembly of higher-order supramolecular frameworks from discrete molecular entities still represents a formidable challenge. In this work, a novel metallo-organic cage [Zn12L4] was assembled based on a triphenylene-cored hexapod terpyridine ligand. Synchotron X-ray analysis revealed a pair of enantiomeric cages in the crystal with flexible ligands twisted clockwise or anticlockwise due to steric hindrance in the structure. Interestingly, due to the strong π–π intermolecular interaction between triphenylene units, a controlled hierarchical packing of sphere-like cages in the crystal was established having a sparse packing mode with huge channels of around 3.6 nm diameter. This research sheds light on the design of strong π–π interactions in supramolecular hierarchical packing and materials science. 

Poly(pyridinium salts) (PPSs) with positive charges on the backbones were designed and synthesized from the transformation of bispyrylium salts. Such materials exhibited good uptake capacity for rhenium capture from water, and excellent selectivity of ReO 4 − from competing anions. Furthermore, the advantages of facile synthesis and large-scale preparation make this material promising for practical use in industry. 

Abstract Understanding how alien species assemble is crucial for predicting changes to community structure caused by biological invasions and for directing management strategies for alien species, but patterns and drivers of alien species assemblages remain poorly understood relative to native species. Climate has been suggested as a crucial filter of invasion-driven homogenization of biodiversity. However, it remains unclear which climatic factors drive the assemblage of alien species. Here, we compiled global data at both grid scale (2,653 native and 2,806 current grids with a resolution of 2° × 2°) and administrative scale (271 native and 297 current nations and sub-nations) on the distributions of 361 alien amphibians and reptiles (herpetofauna), the most threatened vertebrate group on the planet. We found that geographical distance, a proxy for natural dispersal barriers, was the dominant variable contributing to alien herpetofaunal assemblage in native ranges. In contrast, climatic factors explained more unique variation in alien herpetofaunal assemblage after than before invasions. This pattern was driven by extremely high temperatures and precipitation seasonality, 2 hallmarks of global climate change, and bilateral trade which can account for the alien assemblage after invasions. Our results indicated that human-assisted species introductions combined with climate change may accelerate the reorganization of global species distributions.