Chlorocholine Perchlorate is an Organic Ferroelectric with Two-Step Ladder-like Dielectric, Second Harmonic Generation Effects, and Ferroelectricity.

The organic salt chlorocholine perchlorate [ClCH2 CH2 N(CH3 )3 ⋅ClO4 ] (CCP) is found to be a molecular ferroelectric with a high theoretical spontaneous polarization (Ps) value up to 17.09 µC cm-2 . CCP exhibits two successive order-disorder phase transition at 332 and 365 K with space groups changing from Cc to Cmc21 and then P63 /mmc, accompanied by unusual two-step ladder-like dielectric, SHG signal with obvious "on/off" contrasts. These findingings provides a further instance of exploring successive thermal-stimuli multi-responsive switching materials applied as switches and sensors.

Highly Stable Europium(III) Tetrahedral (Eu4L4)(phen)4 Cage: Structure, Luminescence Properties, and Cellular Imaging.

Luminescent lanthanide cages have many potential applications in guest recognition, sensing, magnetic resonance imaging (MRI), and bioimaging. However, these polynuclear lanthanide assemblies' poor stability, dispersity, and luminescence properties have significantly constrained their practical applications. Furthermore, it is still a huge challenge to simultaneously synthesize and design lanthanide organic polyhedra with high stability and quantum yield. Herein, we demonstrate a simple and robust strategy to improve the rigidity, chemical stability, and luminescence of an Eu(III) tetrahedral cage by introducing the conjugated planar auxiliary phen ligand. The self-assembled tetrahedral cage, (Eu4L4)(phen)4 [L = (4,4',4″-tris(4,4,4-trifluoro-1,3-dioxobutyl)-triphenylamine), phen = 1,10-phenanthroline], exhibited characteristic luminescence of Eu3+ ions with high quantum yield (41%) and long lifetime (131 µs) in toluene (1.0 × 10-6 M). Moreover, the Eu(III) cage was stable in water and even in an aqueous solution with a pH range of 1-14. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and cellular imaging revealed that the Pluronic F127-coated hybrid material, (Eu4L4)(phen)4@F127, exhibited low cytotoxicity, good biocompatibility, and cellular imaging ability, which may inspire more insights into the development of lanthanide organic polyhedra (LOPs) for potential biomedical applications.