title: (E)-4-Methyl-N-((quinolin-2-yl)ethylidene)aniline as ligand for IIB supramolecular complexes: synthesis, structure, aggregation-induced emission enhancement and application in PMMA-doped hybrid material.
abstract: Judicious structural design employing 2-quinolinecarboxaldehyde and 4-methylaniline was used to generate the Schiff base ligand (E)-4-methyl-N-((quinolin-2-yl)ethylidene)aniline (L). Five IIB complexes, namely, [ZnLCl2] (1), [ZnL(NO3)2] (2), [ZnL(OAc)2]3(3), [CdL(OAc)2]3(4), and [HgLCl2] (5) have been synthesized based on L. Single-crystal X-ray diffraction analysis indicates that complexes 1, 3 and 4 exhibit 3D networks, whereas 2 and 5 form 2D layers and 1D chains, respectively. TD-DFT calculations show a good correlation with the UV-vis absorption assigned to π → π* intraligand transitions. Furthermore, complexes 1-5 displayed strong greenish luminescent emissions (518-524 nm) in the aggregate state but weak emissions in solution (aggregation-induced emission enhancement), which may be due to the existence of C-HCl/O hydrogen bonding and ππ stacking interactions, resulting in restriction of intramolecular rotation (RIR). Variable-concentration1H NMR studies suggested that the aggregates undergo intramolecular changes in conformation due to intermolecular interactions. Moreover, the emission intensity and lifetime exhibited obvious increases induced by mechanical grinding and temperature reduction, which were also attributed to AIEE properties. Subsequently, complex 1 was incorporated into poly(methyl methacrylate) (PMMA), whereby 1-PMMA exhibited enhanced emission intensity (20-fold increase in comparison with that of 1), which offers opportunities for use in plastic greenhouses to increase leaf photosynthesis.
authors.affiliation: MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China. fanruiqing@hit.edu.cn ylyang@hit.edu.cn.
authors.forename: Ani
authors.initials: A
authors.lastname: Wang
authors.affiliation: MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China. fanruiqing@hit.edu.cn ylyang@hit.edu.cn.
authors.forename: Ruiqing
authors.initials: R
authors.lastname: Fan
authors.affiliation: MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China. fanruiqing@hit.edu.cn ylyang@hit.edu.cn.
authors.forename: Yuwei
authors.initials: Y
authors.lastname: Dong
authors.affiliation: MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China. fanruiqing@hit.edu.cn ylyang@hit.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China. fanruiqing@hit.edu.cn ylyang@hit.edu.cn.
authors.forename: Yang
authors.initials: Y
authors.lastname: Song
authors.affiliation: MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China. fanruiqing@hit.edu.cn ylyang@hit.edu.cn.
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.affiliation: MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China. fanruiqing@hit.edu.cn ylyang@hit.edu.cn.
authors.forename: Sue
authors.initials: S
authors.lastname: Hao
authors.affiliation: MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China. fanruiqing@hit.edu.cn ylyang@hit.edu.cn.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Liu
authors.affiliation: MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China. fanruiqing@hit.edu.cn ylyang@hit.edu.cn.
authors.forename: Yulin
authors.initials: Y
authors.lastname: Yang