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Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides
Published on: November 21, 2013
Distinct differences in self-assembly of aromatic linear dicarboxylic acids
Christoph Heininger1, Lorenz Kampschulte, Wolfgang M Heckl
1Department for Earth and Environmental Sciences, Ludwig-Maximilians-University and Center for NanoScience (CeNS), Theresienstrasse 41, DE-80333 Munchen, Germany.
Langmuir : the ACS Journal of Surfaces and Colloids
|December 19, 2008
Summary
Three aromatic dicarboxylic acids self-assemble into ordered monolayers on graphite. Differences in molecular structure, adsorption geometry, and energy explain variations in layer stability and order, as confirmed by scanning tunneling microscopy and DFT calculations.
Area of Science:
- Supramolecular chemistry
- Surface science
- Materials science
Background:
- Aromatic dicarboxylic acids exhibit structural similarities, including two interconnected aromatic moieties and linearly configured carboxylic groups.
- These molecules are known to form ordered monolayers at liquid-solid interfaces.
Purpose of the Study:
- To investigate the self-assembly of 2,6-naphthalenedicarboxylic acid (NDA), 4,4'-biphenyldicarboxylic acid (BPDA), and 4,4'-stilbenedicarboxylic acid (SDA) into two-dimensionally ordered supramolecular structures.
- To analyze the factors influencing the stability, domain size, and order of these adsorbate layers.
Main Methods:
- Scanning tunneling microscopy (STM) was employed to study the self-assembly at the liquid-solid interface on a graphite substrate.
- Density functional theory (DFT) calculations were used to support the analysis of experimental observations.
Main Results:
- All three compounds formed ordered monolayers, characterized by dense packing of one-dimensionally hydrogen-bonded rows.
- Distinct differences in adsorbate layer stability, average domain size, and degree of order were observed among NDA, BPDA, and SDA.
- These differences were correlated with variations in molecular structure, adsorption geometry, and adsorption energy.
Conclusions:
- The molecular structure, adsorption geometry, and adsorption energy are critical determinants of the self-assembly behavior and resulting supramolecular structure of aromatic dicarboxylic acids.
- Understanding these structure-property relationships is essential for designing and controlling supramolecular architectures at interfaces.
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