1. Toluene Valence and Rydberg Excitations as Studied by ab initio Calculations and Vacuum Ultraviolet (VUV) Synchrotron Radiation
- Author
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Paulo Limão-Vieira, Benilde Simões Mendes, Denis Duflot, Søren Vrønning Hoffmann, C. Serralheiro, Nykola C. Jones, Nicholas J Mason, F. Ferreira da Silva, Centro de Engenharia Mecânica e Sustentabilidade de Recursos (MEtRICS), Faculdade de Ciências e Tecnologia = School of Science & Technology (FCT NOVA), Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade Nova de Lisboa = NOVA University Lisbon (NOVA), Physico-Chimie Moléculaire Théorique (PCMT), Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Department of Physics and Astronomy [Aarhus], Aarhus University [Aarhus], School of Physical Sciences [Milton Keynes], Faculty of Science, Technology, Engineering and Mathematics [Milton Keynes], The Open University [Milton Keynes] (OU)-The Open University [Milton Keynes] (OU), Centro de Física e Investigação Tecnológica [Lisboa] (CEFITEC), Departamento de Fìsica [Lisboa] (DF), Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Faculdade de Ciências e Tecnologia = School of Science & Technology (FCT NOVA), Portuguese National Funding Agency FCT-MEC through researcher and sabbatical grants, IF-FCT IF/00380/2014 and SFRH/BSAB/105792/2014, research grants PTDC/FIS-ATO/1832/2012 and UID/FIS/00068/2013, and ANR-11-LABX-0005,Cappa,Physiques et Chimie de l'Environnement Atmosphérique(2011)
- Subjects
Vacuum ,010504 meteorology & atmospheric sciences ,Ultraviolet Rays ,Synchrotron radiation ,Electrons ,7. Clean energy ,01 natural sciences ,Electron spectroscopy ,symbols.namesake ,Ab initio quantum chemistry methods ,0103 physical sciences ,Molecule ,Physical and Theoretical Chemistry ,Spectroscopy ,0105 earth and related environmental sciences ,Photolysis ,Valence (chemistry) ,010304 chemical physics ,Atmosphere ,Chemistry ,Photodissociation ,Absorption, Radiation ,13. Climate action ,Rydberg formula ,symbols ,Quantum Theory ,Spectrophotometry, Ultraviolet ,[PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph] ,Atomic physics ,Synchrotrons ,Toluene - Abstract
International audience; The electronic spectroscopy of isolated toluene in the gas phase has been investigated using high-resolution photoabsorption spectroscopy in the 4.0–10.8 eV energy range, with absolute cross-section measurements derived. We present the first set of ab initio calculations (vertical energies and oscillator strengths), which we use in the assignment of valence and Rydberg transitions of the toluene molecule. The spectrum reveals several new features not previously reported in the literature, with particular relevance to 7.989 and 8.958 eV, which are here tentatively assigned to the π*(17a′) ← σ(15a′) and 1π*(10a″) ← 1π(14a′) transitions, respectively. The measured absolute photoabsorption cross sections have been used to calculate the photolysis lifetime of toluene in the upper stratosphere (20–50 km).
- Published
- 2015