X-ray spectroscopy characterization of self-assembled monolayers of nitrile-substituted oligo(phenylene ethynylene)s with variable chain length
Self-assembled monolayers (SAMs) of nitrile-substituted oligo(phenylene ethynylene) thiols (NC-OPEn) with a variable chain length n (n ranging from one to three structural units) on Au(111) were studied by synchrotron-based high-resolution X-ray photoelectron spectroscopy and near-edge absorption fi...
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Beilstein-Institut
2012-01-01
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| Series: | Beilstein Journal of Nanotechnology |
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| Online Access: | https://doi.org/10.3762/bjnano.3.2 |
| _version_ | 1811259122186715136 |
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| author | Hicham Hamoudi Ping Kao Alexei Nefedov David L. Allara Michael Zharnikov |
| author_facet | Hicham Hamoudi Ping Kao Alexei Nefedov David L. Allara Michael Zharnikov |
| author_sort | Hicham Hamoudi |
| collection | DOAJ |
| description | Self-assembled monolayers (SAMs) of nitrile-substituted oligo(phenylene ethynylene) thiols (NC-OPEn) with a variable chain length n (n ranging from one to three structural units) on Au(111) were studied by synchrotron-based high-resolution X-ray photoelectron spectroscopy and near-edge absorption fine-structure spectroscopy. The experimental data suggest that the NC-OPEn molecules form well-defined SAMs on Au(111), with all the molecules bound to the substrate through the gold–thiolate anchor and the nitrile tail groups located at the SAM–ambient interface. The packing density in these SAMs was found to be close to that of alkanethiolate monolayers on Au(111), independent of the chain length. Similar behavior was found for the molecular inclination, with an average tilt angle of ~33–36° for all the target systems. In contrast, the average twist of the OPEn backbone (planar conformation) was found to depend on the molecular length, being close to 45° for the films comprising the short OPE chains and ~53.5° for the long chains. Analysis of the data suggests that the attachment of the nitrile moiety, which served as a spectroscopic marker group, to the OPEn backbone did not significantly affect the molecular orientation in the SAMs. |
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| institution | Directory Open Access Journal |
| issn | 2190-4286 |
| language | English |
| last_indexed | 2024-04-12T18:25:42Z |
| publishDate | 2012-01-01 |
| publisher | Beilstein-Institut |
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| spelling | doaj.art-cb6f1723aec842879a3e6f93fd41af3e2022-12-22T03:21:16ZengBeilstein-InstitutBeilstein Journal of Nanotechnology2190-42862012-01-0131122410.3762/bjnano.3.22190-4286-3-2X-ray spectroscopy characterization of self-assembled monolayers of nitrile-substituted oligo(phenylene ethynylene)s with variable chain lengthHicham Hamoudi0Ping Kao1Alexei Nefedov2David L. Allara3Michael Zharnikov4Angewandte Physikalische Chemie, Universität Heidelberg, D-69120 Heidelberg, GermanyDepartments of Chemistry and Material Science, Pennsylvania State University, University Park, PA16802, USAInstitut für Funktionelle Grenzflächen, Karlsruher Institut für Technologie, D-76344 Eggenstein-Leopoldshafen, GermanyDepartments of Chemistry and Material Science, Pennsylvania State University, University Park, PA16802, USAAngewandte Physikalische Chemie, Universität Heidelberg, D-69120 Heidelberg, GermanySelf-assembled monolayers (SAMs) of nitrile-substituted oligo(phenylene ethynylene) thiols (NC-OPEn) with a variable chain length n (n ranging from one to three structural units) on Au(111) were studied by synchrotron-based high-resolution X-ray photoelectron spectroscopy and near-edge absorption fine-structure spectroscopy. The experimental data suggest that the NC-OPEn molecules form well-defined SAMs on Au(111), with all the molecules bound to the substrate through the gold–thiolate anchor and the nitrile tail groups located at the SAM–ambient interface. The packing density in these SAMs was found to be close to that of alkanethiolate monolayers on Au(111), independent of the chain length. Similar behavior was found for the molecular inclination, with an average tilt angle of ~33–36° for all the target systems. In contrast, the average twist of the OPEn backbone (planar conformation) was found to depend on the molecular length, being close to 45° for the films comprising the short OPE chains and ~53.5° for the long chains. Analysis of the data suggests that the attachment of the nitrile moiety, which served as a spectroscopic marker group, to the OPEn backbone did not significantly affect the molecular orientation in the SAMs.https://doi.org/10.3762/bjnano.3.2nitrile substitutionoligo(phenylene ethynylene)self-assembled monolayerstwist angleX-ray absorption spectroscopy |
| spellingShingle | Hicham Hamoudi Ping Kao Alexei Nefedov David L. Allara Michael Zharnikov X-ray spectroscopy characterization of self-assembled monolayers of nitrile-substituted oligo(phenylene ethynylene)s with variable chain length Beilstein Journal of Nanotechnology nitrile substitution oligo(phenylene ethynylene) self-assembled monolayers twist angle X-ray absorption spectroscopy |
| title | X-ray spectroscopy characterization of self-assembled monolayers of nitrile-substituted oligo(phenylene ethynylene)s with variable chain length |
| title_full | X-ray spectroscopy characterization of self-assembled monolayers of nitrile-substituted oligo(phenylene ethynylene)s with variable chain length |
| title_fullStr | X-ray spectroscopy characterization of self-assembled monolayers of nitrile-substituted oligo(phenylene ethynylene)s with variable chain length |
| title_full_unstemmed | X-ray spectroscopy characterization of self-assembled monolayers of nitrile-substituted oligo(phenylene ethynylene)s with variable chain length |
| title_short | X-ray spectroscopy characterization of self-assembled monolayers of nitrile-substituted oligo(phenylene ethynylene)s with variable chain length |
| title_sort | x ray spectroscopy characterization of self assembled monolayers of nitrile substituted oligo phenylene ethynylene s with variable chain length |
| topic | nitrile substitution oligo(phenylene ethynylene) self-assembled monolayers twist angle X-ray absorption spectroscopy |
| url | https://doi.org/10.3762/bjnano.3.2 |
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