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Unusual intermolecular π-stacking in a new charge transfer salt of pyrene (Py), (Py) 2 + (Ga 2 Cl 7 ) − , has been observed. The structure obtained by single crystal X-ray crystallography indicates π-stacks of pyrene which were analyzed using a combination of density functional theory and the analysis of the bond length alternation patterns in the pyrene molecules in different charge states. There are relatively few crystal structures of charge transfer salts of pyrene in the literature, and this structure shows a unique charge separation in which half of the pyrenes are nearly neutral while the other half carry approximately +1 charge in an alternating fashion along the 1D stacks balancing one electron charge transfer to each (Ga 2 Cl 7 ) − anion. The charge localization is attributed to the incomplete inter-pyrene overlap of the singly occupied molecular orbitals.
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Superstructural diversity in salt-cocrystals: higher-order hydrogen-bonded assemblies formed using U-shaped dications and with assistance of π − –π stacking
Salt cocrystals with components that assemble by hydrogen bonds and aromatic anion–molecule stacks (π − –π stacks) are reported. U-shaped bipyridines and an isocoumarin carboxylic acid self-assemble to form 5-, 6-, and 10-component aggregates with components in double and quadruple face-to-face stacks. DFT calculations support the π − –π stacks to help stabilize the salt cocrystals.
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- Award ID(s):
- 1708673
- PAR ID:
- 10254082
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 56
- Issue:
- 49
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 6708 to 6710
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D0CC02671A
