Added Alkane Allows Thermal Thinning of Supramolecular Columns by Forming Superlattice-An X-ray and Neutron Study.
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.
Department of Materials Science and Engineering, University of Sheffield , Sheffield S1 3JD, U.K.
Ming-Huei
MH
Yen
Department of Materials Science and Engineering, University of Sheffield , Sheffield S1 3JD, U.K.
Jitrin
J
Chaiprapa
Department of Materials Science and Engineering, University of Sheffield , Sheffield S1 3JD, U.K.
Xiangbing
X
Zeng
Department of Physics, Zhejiang Sci-Tech University , Hangzhou 310018, China.
Yongsong
Y
Liu
Department of Chemistry, University of Hull , Hull HU6 7RX, U.K.|Institute of Chemistry, Timisoara of Romanian Academy , Timisoara 300223, Romania.
Liliana
L
Cseh
Department of Chemistry, University of Hull , Hull HU6 7RX, U.K.
Georg H
GH
Mehl
Department of Materials Science and Engineering, University of Sheffield , Sheffield S1 3JD, U.K.|Department of Physics, Zhejiang Sci-Tech University , Hangzhou 310018, China.
Goran
G
Ungar