Orientational changes of supported chiral 2,2'-dihydroxy-1,1'binaphthyl molecules
| Autor: | Sabine Gerlach, Thierry Verbiest, Tobias Lünskens, Martin Thämer, Ueli Heiz, Aras Kartouzian, Philipp Heister |
|---|---|
| Rok vydání: | 2014 |
| Předmět: |
Chemistry
General Physics and Astronomy 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology Rotation 01 natural sciences 0104 chemical sciences Thin glass Crystallography Orientation (geometry) Molecular film Molecule Physical and Theoretical Chemistry Enantiomer Well-defined 0210 nano-technology Chirality (chemistry) |
| Zdroj: | Physical chemistry chemical physics : PCCP. 16(16) |
| ISSN: | 1463-9084 |
| Popis: | Well defined thin molecular films of 2,2'-dihydroxy-1,1'binaphthyl (binol) molecules at coverages between 5 × 10(15) molecules per cm(2) and 10(17) molecules per cm(2) on thin glass (BK7) substrates were investigated under ultra-high-vacuum (UHV) conditions. Second-Harmonic-Generation Optical-Rotatory-Dispersion measurements (SHG-ORD) were performed using a dedicated spectroscopic setup which allows for the determination of the rotation angle of the SH-signal of two enantiomers. Rotation angles of up to 38 degrees were measured. The chirality of the two enantiomers has been studied at 674 nm (337 nm resonance wavelength) in the transmission mode. Coverage dependent orientation evolution of binol molecular films was revealed by precise monitoring of the surface coverage while performing SHG-ORD experiments. We show that the molecules reach their final orientation at a surface coverage of 5 × 10(16) molecules per cm(2). From the obtained experimental data the ratio of chiral and achiral susceptibility components could be calculated and was observed to change with coverage. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|