Electron impact ionisation and UV absorption study of α- and β-pinene

Authors :: Kubala, D.
Drage, E.A.
Al-Faydhi, A.M.E.
Kočíšek, J.
Papp, P.
Matejčík, V.
Mach, P.
Urban, J.
Limão-Vieira, P.
Hoffmann, S.V.
Matejčík, Š.
Mason, N.J.
Source :: International Journal of Mass Spectrometry. Feb2009, Vol. 280 Issue 1-3, p169-173. 5p.
Publication Year :: 2009
Abstract: Abstract: We have performed a coordinated set of experiments to measure the electron impact ionisation and UV photoabsorption cross sections of α- and β-pinene. The adiabatic ionisation energies of α- and β-pinene were derived from experiment and found to be 8.3 and 8.6eV which compared well with high-level quantum chemical calculations (G3MP2) yielding values of 8.29 and 8.41eV. Additionally, vertical ionisation energies of 8.62 and 8.96eV were calculated using an OVGF method. UV photoabsorption cross sections were measured using a high-resolution synchrotron radiation source and electronic states interpreted on the basis of the TD quantum chemical methods. [Copyright &y& Elsevier]