Two rhomboidal metallacycles based on metal‐coordination‐driven self‐assembly are presented. Because metal‐coordination interactions restrict the rotation of phenyl groups on tetraphenylethene units, these metallacycles were emissive both in solution and in solid state, and their aggregation‐induced emission properties were well‐retained. Moreover, the rhomboidal metallacyclic structures offer a platform for intermolecular packing beneficial for the formation of liquid crystalline phases. Therefore, although neither of building blocks shows mesogenic properties, both thermotropic and lyotropic (in DMF) mesophases were observed in one of metallacycles, indicating that mesophases could be induced by metal‐coordination interactions. This study not only reveals the mechanism for the formation of cavity‐cored liquid crystals, but also provides a convenient approach to preparing supramolecular luminescent liquid crystals, which will serve as good candidates for chemo sensors and liquid crystal displays.

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The direct construction of protein-like multicompartment nanoparticles (MCNs) possessing hydrophilic/ hydrophobic subdomains is a contemporary challenge. Herein, we present the first example of such MCNs via self-assembly of the specially designed A(BC) 20 star polymer in an aqueous solution. The topology of the 21-arm star polymer, poly(ethylene glycol)[poly(acrylic acid)-block-polystyrene] 20 [PEG(PAA-b-PS) 20 ], is the key to simultaneously form hydrophilic/hydrophobic subdomains of nanoparticles during self-assembling, as the watersoluble PAA blocks are confined in the core, resulting in hydrophilic subdomains. The volume ratio of PS to PAA (V PS /V PAA ) is found to be the main factor that determines the morphology of MCNs; besides micelles and vesicles, strings consisting of onedimensional (1D) alignment of single-star polymers were found for the first time, as confirmed by transmission electron microscopy (TEM) and cryo-TEM. Lastly, a new mechanism for the assembly of the star polymers was proposed based on the investigations of PEG(PAA-b-PS) 20 self-assembly under different water contents, concentrations, and pH values. The MCNs reported in this work may find various applications in, e.g., co-delivery of drugs and heterogeneous catalysis.

Block copolymers (BCPs) comprising of a poly(methyl methacrylate) (PMMA) block and a poly(cholesteryloxyhexyl methacrylate block (PChMA) were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. The self-assembly of the liquid crystalline block copolymers was characterized by differential scanning calorimetry (DSC), 1 polarized optical microscopy (POM) and synchrotron-based small-angle X-ray scattering (SAXS). The results indicate the formation of both tilted and non-tilted chiral smectic (SmC* and SmA*) phases. A phase transition from SmA* to SmC* phase on cooling was observed for BCPs, but not for PChMA homopolymers. The layer spacing (5.00 ± 0.18 nm) between those can be controlled to maintain the number of ChMA units whilst varying the lengths of the PMMA block, introducing thus systematically the SmC* phase. Furthermore, BCPs with short PMMA block showed inversion of chirality at specific temperatures; while for PChMA attached with long PMMA block no chirality inversion was observed. This mode of chirality switching, investigated by CD, NMR, and theoretical studies, is associated with the methyl substituents in the backbone affecting the packing of the polymers. The basic rules, described here, have the potential to be implemented for the design of a wide range of functional materials where helix-helix conversion is of use. helix-helix transitions in nature and has the potential to be exploited further for artificial systems. ASSOCIATED CONTENT Supporting InformationExperimental methods, NMR, DSC, POM, SAXS, WAXS, CD and theoretical calculation results are included in the supporting information.

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