Added alkane allows thermal thinning of supramolecular columns by forming superlattice - an X-ray and neutron study

Yen, Ming Huei; Chaiprapa, Jitrin; Zeng, Xiangbing; Liu, Yongsong; Cseh, Liliana; Mehl, Georg H.; Ungar, Goran

Abstract

We report a columnar superlattice formed by blends of dendron-like Li 3,4,5-tris(n-alkoxy)benzoates with n-alkanes. Without the alkane, the wedge-shaped molecules form liquid crystal columns with 3 dendrons in a supramolecular disk. The same structure exists in the blend, but on heating one dendron is expelled from the disks in every third column and is replaced by the alkane. This superlattice of unequal columns is confirmed by complementary X-ray and neutron diffraction studies. Lateral thermal expansion of dendrons normally leads to the expulsion of excess molecules from the column, reducing the column diameter. However in the already narrow columns of pure Li salt, expulsion of one of only three dendrons in a disk is not viable. The added alkane facilitates the expulsion, as it replaces the missing dendron. Replacing the alkane with a functional compound can potentially lead to active nanoarrays with relatively large periodicity by using only small molecules.

Citation

Yen, M. H., Chaiprapa, J., Zeng, X., Liu, Y., Cseh, L., Mehl, G. H., & Ungar, G. (2016). Added alkane allows thermal thinning of supramolecular columns by forming superlattice - an X-ray and neutron study. Journal of the American Chemical Society, 138(18), 5757-5760. https://doi.org/10.1021/jacs.6b01172

• Acceptance Date: Apr 22, 2016
• Online Publication Date: Apr 27, 2016
• Publication Date: May 11, 2016
• Deposit Date: Apr 26, 2016
• Publicly Available Date: Apr 27, 2016
• Journal: Journal of the American Chemical Society
• Print ISSN: 0002-7863
• Electronic ISSN: 1520-5126
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 138
• Issue: 18
• Pages: 5757-5760
• DOI: https://doi.org/10.1021/jacs.6b01172
• Keywords: Alkane, Thermal thinning
• Public URL: https://hull-repository.worktribe.com/output/436963
• Publisher URL: http://pubs.acs.org/doi/abs/10.1021/jacs.6b01172
• Additional Information: This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of the American Chemical Society, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/jacs.6b01172