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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(39):11936-11940
An unprecedented crystal‐packing arrangement of a tetramethoxy‐bay‐substituted perylene bisimide (PBI) consists of three crystallographically independent molecules, that is, an achiral ( AC ) PBI of saddle‐shaped geometry along with two pairs of propeller‐like twisted (P )‐ and (M )‐enantiomeric PBI frameworks. All these five conformations are observed within a single π‐stack revealing an intriguing packing sequence with an inversion of chirality from P to M via AC . Nudged elastic band calculations for the isolated molecule show that AC is a local minimum of the P to M interconversion path. In addition, two minor conformations were observed in the crystal, one of which resembles a transition‐state molecule. Theoretical studies of dimeric and trimeric stacks reveal that the coexistence of all these structures in the crystal lattice is aided by the strong dispersion interactions between PBI cores and perfectly interdigitated dodecyl chains which stabilize energetically higher conformations. 相似文献
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Xinbo Wen Agnieszka Nowak‐Krl Oliver Nagler Felix Kraus Na Zhu Nan Zheng Matthias Müller David Schmidt Zengqi Xie Frank Würthner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(37):13185-13189
By introduction of four hydroxy (HO) groups into the two perylene bisimide (PBI) bay areas, new HO‐PBI ligands were obtained which upon deprotonation can complex ZnII ions and photosensitize semiconductive zinc oxide thin films. Such coordination is beneficial for dispersing PBI photosensitizer molecules evenly into metal oxide films to fabricate organic–inorganic hybrid interlayers for organic solar cells. Supported by the photoconductive effect of the ZnO: HO‐PBI hybrid interlayers, improved electron collection and transportation is achieved in fullerene and non‐fullerene polymer solar cell devices, leading to remarkable power conversion efficiencies of up to 15.95 % for a non‐fullerene based organic solar cell. 相似文献
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Congdi Shang Dr. Gang Wang Dr. Ke Liu Qingwei Jiang Prof. Fengyi Liu Prof. Pi-Tai Chou Prof. Yu Fang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(22):8657-8663
The origin of the positive temperature effect in fluorescence emission of a newly designed perylene bisimide (PBI) derivative with two naphthyl units containing ortho-methoxy group (NM) at its bay positions (PBI-2NM) was elucidated. A key point is the finding of a weak hydrogen bond (<5.0 kcal mol−1) between the methoxy group of the NM unit and a nearby hydrogen atom of the PBI core. It is the bonding that drives co-planarization of the different aromatic units, resulting in delocalization of the π-electrons of the compound as synthesized, inducing fluorescence quenching via intramolecular charge transfer (ICT). With increasing temperature, the co-planar structure could be distorted in part, resulting in a decreased degree of ICT, and hence leading to enhanced fluorescence emission. The unique positive temperature effect in emission induced by H-bond-driven co-planarization may pave a new avenue in designing functional molecular systems complementary to conventional methods. 相似文献
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Adam Ashcraft Kaixuan Liu Dr. Arindam Mukhopadhyay Victor Paulino Chuan Liu Brianna Bernard Dalia Husainy Tina Phan Prof. Dr. Jean-Hubert Olivier 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(19):7557-7563
Locking-in the conformation of supramolecular assemblies provides a new avenue to regulate the (opto)electronic properties of robust nanoscale objects. In the present contribution, we show that the covalent tethering of a perylene bisimide (PBI)-derived supramolecular polymer with a molecular locker enables the formation of a locked superstructure equipped with emergent structure–function relationships. Experiments that exploit variable-temperature ground-state electronic absorption spectroscopy unambiguously demonstrate that the excitonic coupling between nearest neighboring units in the tethered superstructure is preserved at a temperature (371 K) where the pristine, non-covalent assembly exists exclusively in a molecularly dissolved state. A close examination of the solid-state morphologies reveals that the locked superstructure engenders the formation of hierarchical 1D materials which are not achievable by unlocked assemblies. To complement these structural attributes, we further demonstrate that covalently tethering a supramolecular polymer built from PBI subunits enables the emergence of electronic properties not evidenced in non-covalent assemblies. Using cyclic voltammetry experiments, the elucidation of the potentiometric properties of the locked superstructure reveals a 100-mV stabilization of the conduction band energy when compared to that recorded for the non-covalent assembly. 相似文献
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Cheng Li Xianxin Wu Xinyu Sui Hongbo Wu Chao Wang Guitao Feng Yonggang Wu Feng Liu Xinfeng Liu Zheng Tang Weiwei Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(43):15678-15686
The crystalline cooperativity of the donor and acceptor segment in double‐cable conjugated polymers plays an important role in the nanophase separation and photovoltaic performance in single‐component organic solar cells (SCOSCs). Two double‐cable conjugated polymers with the same conjugated backbone and perylene bisimide (PBI) side units were designed in which PBIs were positioned symmetrically and perpendicularly ( P1 ) and asymmetrically and slantingly ( P2 ) along the conjugated backbones. After thermal annealing, both conjugated backbones and PBI side units in P1 tend to form ordered nanostructures, while PBI side units in P2 dominated the crystallization and hamper the crystallization of conjugated backbones. P1 showed good crystalline cooperativity between conjugated backbones and PBI side units, resulting in improved power conversion efficiencies (PCEs) up to 3.43 % in SCOSCs, while P2 with poor crystalline cooperativity exhibited PCEs below 2.42 %. 相似文献
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