| Title: | Chiral Porphyrin Assemblies Investigated by a Modified Reflectance Anisotropy Spectroscopy Spectrometer |
| Author(s): | Tomei I; Bonanni B; Sgarlata A; Fanfoni M; Martini R; Di Filippo I; Magna G; Stefanelli M; Monti D; Paolesse R; Goletti C; |
| Address: | "Department of Physics, Universita di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Roma, Italy. Department of Chemical Science and Technologies, Universita di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome, Italy. Department of Chemistry, Sapienza Universita di Roma, Piazzale Aldo Moro 5, 00185 Rome, Italy" |
| DOI: | 10.3390/molecules28083471 |
| ISSN/ISBN: | 1420-3049 (Electronic) 1420-3049 (Linking) |
| Abstract: | "Reflectance anisotropy spectroscopy (RAS) has been largely used to investigate organic compounds: Langmuir-Blodgett and Langmuir-Schaeffer layers, the organic molecular beam epitaxy growth in situ and in real time, thin and ultrathin organic films exposed to volatiles, in ultra-high vacuum (UHV), in controlled atmosphere and even in liquid. In all these cases, porphyrins and porphyrin-related compounds have often been used, taking advantage of the peculiar characteristics of RAS with respect to other techniques. The technical modification of a RAS spectrometer (CD-RAS: circular dichroism RAS) allows us to investigate the circular dichroism of samples instead of the normally studied linear dichroism: CD-RAS measures (in transmission mode) the anisotropy of the optical properties of a sample under right and left circularly polarized light. Although commercial spectrometers exist to measure the circular dichroism of substances, the 'open structure' of this new spectrometer and its higher flexibility in design makes it possible to couple it with UHV systems or other experimental configurations. The importance of chirality in the development of organic materials (from solutions to the solid state, as thin layers deposited-in liquid or in vacuum-on transparent substrates) could open interesting possibilities to a development in the investigation of the chirality of organic and biological layers. In this manuscript, after the detailed explanation of the CD-RAS technique, some calibration tests with chiral porphyrin assemblies in solution or deposited in solid film are reported to demonstrate the quality of the results, comparing curves obtained with CD-RAS and a commercial spectrometer" |
| Keywords: | chiral layers chirality circular dichroism porphyrins reflectance anisotropy spectroscopy supramolecular chirality; |
| Notes: | "PubMed-not-MEDLINETomei, Ilaria Bonanni, Beatrice Sgarlata, Anna Fanfoni, Massimo Martini, Roberto Di Filippo, Ilaria Magna, Gabriele Stefanelli, Manuela Monti, Donato Paolesse, Roberto Goletti, Claudio eng 2017EKCS35_002/MUR-PRIN/ project ASPIRE E84I20000220005/University of Rome Tor Vergata/ Switzerland 2023/04/28 Molecules. 2023 Apr 14; 28(8):3471. doi: 10.3390/molecules28083471" |
