scholarly journals Isotope and Hydrogen‐Bond Effects on the Self‐Assembly of Macroions in Dilute Solution

2019 ◽  
Vol 25 (71) ◽  
pp. 16288-16293 ◽  
Author(s):  
Hui Li ◽  
Yidan Shen ◽  
Peng Yang ◽  
Jennifer E. S. Szymanowski ◽  
Jiahui Chen ◽  
...  
2018 ◽  
Vol 5 (5) ◽  
pp. 180247 ◽  
Author(s):  
Yuanming Zhang ◽  
Tingting Sun ◽  
Wei Jiang ◽  
Guangting Han

In this paper, the crystalline modification of a rare earth nucleating agent (WBG) for isotactic polypropylene (PP) based on its supramolecular self-assembly was investigated by differential scanning calorimetry, wide-angle X-ray diffraction and polarized optical microscopy. In addition, the relationship between the self-assembly structure of the nucleating agent and the crystalline structure, as well as the possible reason for the self-assembly behaviour, was further studied. The structure evolution of WBG showed that the self-assembly structure changed from a needle-like structure to a dendritic structure with increase in the content of WBG. When the content of WBG exceeded a critical value (0.4 wt%), it self-assembled into a strip structure. This revealed that the structure evolution of WBG contributed to the K β and the crystallization morphology of PP with different content of WBG. In addition, further studies implied that the behaviour of self-assembly was a liquid–solid transformation of WBG, followed by a liquid–liquid phase separation of molten isotactic PP and WBG. The formation of the self-assembly structure was based on the free molecules by hydrogen bond dissociation while being heated, followed by aggregation into another structure by hydrogen bond association while being cooled. Furthermore, self-assembly behaviour depends largely on the interaction between WBG themselves.


2017 ◽  
Vol 24 (Supp02) ◽  
pp. 1850025
Author(s):  
YUFEN HU ◽  
WEI LI ◽  
YAN LU ◽  
ZHONGPING WANG ◽  
XINLI LENG ◽  
...  

The self-assembly structures of 2,2[Formula: see text]:6[Formula: see text],2[Formula: see text]-terpyridine-4[Formula: see text]-carboxylic acid (C[Formula: see text]H[Formula: see text]N3O2; [Formula: see text]) molecules and 3,5-diphenylbenzoic acid (C[Formula: see text]H[Formula: see text]O2; [Formula: see text]) molecules on Ag(110) surface have been investigated by scanning tunneling microscopy (STM) and Density Functional Theory (DFT) calculation. The [Formula: see text] molecules form two different well-organized structures due to the [Formula: see text]–[Formula: see text] stacking and dipole–dipole interactions. When three C atoms of [Formula: see text] molecules are replaced by three N atoms to form [Formula: see text] molecules, the main driving force to form ordered assembly structures of [Formula: see text] molecule is changed to metal–organic coordination bond and hydrogen bond. The dramatic changes of main driving force between [Formula: see text]/Ag(110) and [Formula: see text]/Ag(110) system demonstrate that the N atoms are apt to form metal–organic coordination bond and hydrogen bond but dipole–dipole interactions and [Formula: see text]–[Formula: see text] stacking are relative to C atoms. These findings further reveal that the optimization design of organic molecules could vary the main driving force and then lead to the change of the molecular self-assembly structures.


2019 ◽  
Vol 10 (18) ◽  
pp. 2337-2343 ◽  
Author(s):  
Megan F. Dunn ◽  
Tao Wei ◽  
Ronald N. Zuckermann ◽  
Timothy F. Scott

Mimicking the self-assembly of nucleic acid sequences into double-stranded molecular ladders that incorporate hydrogen bond-based rungs, dynamic covalent interactions enable the fabrication of molecular ladder and grid structures with covalent bond-based rungs.


2009 ◽  
Vol 87 (1) ◽  
pp. 205-211 ◽  
Author(s):  
Barry A Blight ◽  
James A Wisner ◽  
Michael C Jennings

Previous studies have determined that neutral palladium(II) dibromide complexes template the formation of [2]pseudorotaxanes, albeit with weaker affinities than the analogous palladium(II) dichloride species. Here, the self-assembly of both [2]rotaxane (2) and [2]catenane (5) were attempted using a PdBr2L2 centre as the template, resulting in the desired interlocked structures. The structures were confirmed by NMR spectroscopy, CSI-MS, and single crystal X-ray diffraction analyses. [2]Rotaxane 2 was isolated in 53% and [2]catenane 5 in 41% yields. The lower yields observed in comparison to the chloride analogues can be attributed to the reduced template effect of the palladium(II) dibromide subunits, caused by both the poor steric fit of the bromides in the isophthalamide cleft and bromide’s reduced capacity as a hydrogen bond acceptor.Key words: rotaxane, catenane, hydrogen bonding, interlocked, supramolecular chemistry.


Author(s):  
Zhen Lu ◽  
Bogeng Guo ◽  
Yulai Zhao ◽  
Linxi Hou ◽  
Longqiang Xiao

Author(s):  
Igor O. Fritsky ◽  
Henryk Kozłowski ◽  
Elena V. Prisyazhnaya ◽  
Aldona Karaczyn ◽  
Valentina A. Kalibabchuk ◽  
...  

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