Electronic excitation of carbonyl sulphide (COS) by high-resolution vacuum ultraviolet photoabsorption and electron-impact spectroscopy in the energy region from 4 to 11 eV.
J Chem Phys
; 142(6): 064303, 2015 Feb 14.
Article
em En
| MEDLINE
| ID: mdl-25681902
ABSTRACT
The electronic state spectroscopy of carbonyl sulphide, COS, has been investigated using high resolution vacuum ultraviolet photoabsorption spectroscopy and electron energy loss spectroscopy in the energy range of 4.0-10.8 eV. The spectrum reveals several new features not previously reported in the literature. Vibronic structure has been observed, notably in the low energy absorption dipole forbidden band assigned to the (4πâ3π) ((1)Δâ(1)Σ(+)) transition, with a new weak transition assigned to ((1)Σ(-)â(1)Σ(+)) reported here for the first time. The absolute optical oscillator strengths are determined for ground state to (1)Σ(+) and (1)Π transitions. Based on our recent measurements of differential cross sections for the optically allowed ((1)Σ(+) and (1)Π) transitions of COS by electron impact, the optical oscillator strength f0 value and integral cross sections (ICSs) are derived by applying a generalized oscillator strength analysis. Subsequently, ICSs predicted by the scaling are confirmed down to 60 eV in the intermediate energy region. The measured absolute photoabsorption cross sections have been used to calculate the photolysis lifetime of carbonyl sulphide in the upper stratosphere (20-50 km).
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
J Chem Phys
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Portugal