@article{056c2a83a87949019c11809be54a041e,
title = "Valence and Ionic Lowest-Lying Electronic States of Isobutyl Formate Studied by High-Resolution Vacuum Ultraviolet Photoabsorption, Photoelectron Spectroscopy, and Ab Initio Calculations",
abstract = "The highest resolution vacuum ultraviolet photoabsorption spectrum of isobutyl formate, C5H10O2, yet reported is presented over the energy range 4.5-10.7 eV (275.5-118.0 nm) revealing several new spectral features. Valence and Rydberg transitions and their associated vibronic series observed in the photoabsorption spectrum have been assigned in accordance with new ab initio calculations of the vertical excitation energies and oscillator strengths. Calculations have also been carried out to determine the ionization energies and fine structure of the lowest ionic state of isobutyl formate and are compared with a newly recorded photoelectron spectrum (from 9.0 to 27.0 eV). The value of the first ionization energy was determined to be 10.508 eV (adiabatic) and 10.837 eV (vertical). New vibrational structure is observed in the first photoelectron band, predominantly resulting from C-O and Ci=O stretches of the molecule. The photoabsorption cross sections have been used to calculate the photolysis lifetime of isobutyl formate in the upper stratosphere (20-50 km), indicating that the hydroxyl radical processes will be the main loss process for isobutyl formate.",
keywords = "DENSITY-FUNCTIONAL THEORY, GAUSSIAN-BASIS SETS, VUV PHOTOABSORPTION, GAS CHROMATOGRAPHY, MASS SPECTROMETRY, CROSS-SECTION, ABSORPTION, ATOMS, IONIZATION, NITROGEN",
author = "Smialek, {M. A.} and M. {\L}abuda and J. Guthmuller and Hoffmann, {S. V.} and Jones, {N. C.} and MacDonald, {M. A.} and L. Zuin and Mason, {Nigel J.} and Lim{\~a}o-vieira, {Paulo Manuel Assis Loureiro}",
note = "Sem PDF. M.A.S. acknowledges the visiting fellow position in the Molecular Physics group, Open University, U.K. P.L.V. acknowledges his visiting Professor position at The Open University, U.K. and partial funding from the research Grants UID/FIS/00068/2013, SFRH/BSAB/105792/2014, and PTDC/FIS-ATO/1832/2012 through the Portuguese National Funding Agency FCT-MEC. The authors wish to acknowledge the beam time at the ISA synchrotron at Aarhus University, Denmark, supported by the European Union (EU) I3 programme ELISA, Grant Agreement 226716. We also acknowledge the financial support provided by the European Commission through the Access to Research Infrastructure action of the Improving Human Potential Programme. A part of research described in this paper was performed at the Canadian Light Source, which is supported by the Canadian Foundation for Innovation, the Natural Sciences and Engineering Research Council of Canada, the University of Saskatchewan, the Government of Saskatchewan, Western Economic Diversification Canada, the National Research Council Canada, and the Canadian Institutes of Health Research. J.G. and M. L. are thankful to the seventh Framework Programme of the European Union (Grant Agreement 321971). All calculations have been performed at the Academic Center (CI TASK) in Gdansk and at Universitatsrechenzentrum of the Friedrich-Schiller University in Jena.",
year = "2015",
doi = "10.1021/acs.jpca.5b06053",
language = "English",
volume = "119",
pages = "8647--8656",
journal = "Journal of Physical Chemistry A",
issn = "1089-5639",
publisher = "ACS - American Chemical Society",
number = "32",
}