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Most Requested Journal Articles 1Q04-Chemistry and Related
Following is one of the journal articles most requested by researchers using CAS online services.
CAPLUS COPYRIGHT 2004 ACS on STN
The characterization of self-assembled monolayer mol. arrays, which serve as active layers in electronic devices, is an important step toward understanding mol.-scale electronics. To correlate the properties of self-assembled monolayers with their mol. structures, .pi.-conjugated mono- and dithiols and arom. dithiols with an O or S atom between two arom. units were designed and synthesized. Their optical properties were detd. by UV-visible spectroscopy. Their self-assembled monolayer films on Au surfaces were characterized by cyclic voltammetry, grazing incidence FTIR spectroscopy (GI-FTIR), and contact angle and ellipsometry measurements. Increasing the chain length from two to four Ph rings showed a more than linear increase of the intensity of the arom. C:C ring stretch modes in GI-FTIR, indicating that the longer p-phenylene system is oriented toward the surface normal. Similar to oligophenylenes, when the no. of repeat units for oligothiophene is increased, a more than linear increase of the intensity of the C:C stretch and C-H bend modes implies that the longest oligothiophenedithiol mol. is oriented close to the surface normal. Ellipsometry showed a smaller deviation from the calcd. monolayer thickness with increasing no. of thiophene or phenylene rings, corroborating the GI-FTIR data. The conjugated phenylene- and thiophene-based dithiols demonstrate a less tilted mol. orientation with respect to the surface normal with increasing chain length. View full-text pdf document from the American Chemical Society, a participating ChemPort publisher. Updated 5/3/2007 3:19:11 PM
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