Infrared-induced conformational interconversion in carboxylic acids isolated in low-temperature rare-gas matrices |
| |
Affiliation: | 1. Department of Chemistry, University of Helsinki, P.O. Box 55 (A.I. Virtasen aukio 1), Helsinki FIN-00014, Finland;2. Department of Chemistry (CQC),University of Coimbra, Coimbra P-3004-535, Portugal;1. Uzhhorod National University, 46 Pidhirna Str., 88000, Uzhhorod, Ukraine;2. Vlokh Institute of Physical Optics, 23 Dragomanov Str., 79005, Lviv, Ukraine;3. Semiconductor Physics, Chemnitz University of Technology, D-09107, Chemnitz, Germany;4. Institute of Electron Physics, Ukr. Nat. Acad. Sci., 21 Universytetska Str., 88017, Uzhhorod, Ukraine;1. Department of Neurobiology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland;2. Faculty of Foundry Engineering, AGH University of Science and Technology, ul. Reymonta 23, 30-059 Kraków, Poland;3. Institute of Nuclear Physics, Polish Academy of Science, 31-342 Krakow, Poland;4. Faculty of Chemistry, Jagiellonian University, ul. Ingardena 3, 30-060 Kraków, Poland;5. Department of Chemistry, Hankuk University of Foreign Studies, Yongin, Kyunggi-Do, 449-791, South Korea;1. Univ. Perpignan Via Domitia, Laboratoire de Mathématiques et Physique, EA 4217, F-66860 Perpignan, France;2. Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris Est Créteil and Paris Diderot, Institut Pierre Simon Laplace, 61 Avenue du Général de Gaulle, 94010 Créteil Cedex, France;1. Dipartimento di Scienze Fisiche e Chimiche, Università dell’Aquila, Via Vetoio 2, 67100, Coppito, L’Aquila, Italy;2. Sorbonne Universities, UPMC, Laboratoire de Réactivité de Surface UMR CNRS 7197, Tour 43-53, 3rd floor, 4 Pl. Jussieu, 75005, Paris, France;3. Service de Bioénergétique, Biologie Structurale et Mécanismes (SB2SM) CEA, iBiTec-S, Biochimie Biophysique et Biologie Structurale (B3S), I2BC, UMR 9198, F-91191 Gif-sur-Yvette, France |
| |
Abstract: | An overview of our recent studies dealing with infrared-induced conformational interconversion of carboxylic acids isolated in rare-gas matrices is presented. Extensive rotational photoisomerization studies have been performed on formic acid, which is the simplest organic acid enabling this kind of processes. Formic acid has two conformers and interconversion between them can be induced by vibrational excitation. As such, it is an ideal model system to study the conformational dynamics of the carboxylic group. Formic acid molecules were found to be isolated in different local environments within the rare-gas matrices, as shown by the site splitting of the vibrational bands. Narrowband tunable infrared (IR) radiation was used to induce site-selective isomerization processes. The induced changes in the IR absorption spectra allowed for a detailed analysis of the vibrational properties of both conformers of formic acid isolated in solid argon. In particular, derived from the intermode coupling constants the local environment was shown to affects the intramolecular potential energy surface. Tunneling is involved in the rotamerization of formic acid, with the tunneling rate being affected by the local environment. Additionally, formic acid exhibits isomer-selective photodissociation where narrowband IR excitation can control the conformer-dependent photodissociation channels. Tunable IR radiation was also used to promote rotamerization in a series of matrix-isolated dicarboxylic acids (ethanedioic, propanedioic, and 2-butenedioic acids) by exciting the first overtone of the OH stretching mode or a suitable combination mode at similar energies. Efficient isomerization involving rotation around the CO bond was observed in most cases whereas the internal rotation around the CC bond was found to be constrained for ethanedioic and (Z)-2-butenedioic acids. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|