More than Restriction of Twisted Intramolecular Charge Transfer: Three-Dimensional Expanded #-Shaped Cross-Molecular Packing for Emission Enhancement in Aggregates

• Published in: Journal of physical chemistry. C Vol. 116; no. 22; pp. 12187 - 12195
• Main Authors: Qian, Yan, Cai, Minmin, Zhou, Xinhui, Gao, Zhiqiang, Wang, Xupeng, Zhao, Yuezhi, Yan, Xiaohong, Wei, Wei, Xie, Linghai, Huang, Wei
• Format: Journal Article
• Language: English
• Published: Columbus, OH American Chemical Society 07.06.2012
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Photoluminescence; Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Aggregation; Solid state; Monocrystals; Hydrogen bonds; Stacking sequence; Fluorescence; Aggregate; Charge transfer; Organic compounds; Crystal structure
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp212257f

This study developed a new solid-state, highly emissive phenylbenzoxazole-based organic compound, N-(4-(benzo[d]oxazol-2-yl)phenyl)-4-tert-butylbenzamide, which exhibited a distinct aggregation-induced enhanced emission. The solid fluorescence efficiency of the newly developed compound was 50.3%, whereas that in THF solution was only 0.22%. The single-crystal analyses revealed that a specific three-dimensional #-shaped cross stacking between molecules was observed in the solid/aggregated state, driven by specific C–H···π interaction and various hydrogen bonds. The expansion of the cross-dipole stacking into the three-dimensional network was believed to be the dominant factor for the emission enhancement in the solids/aggregates, with respect to the assistant effect of the photoinduced twisted intramolecular charge transfer restriction.