Photoabsorption, photoionization, and neutral-dissociation cross sections of simple hydrocarbons in the vacuum ultraviolet range

• Published in: Journal of electron spectroscopy and related phenomena Vol. 123; no. 2; pp. 225 - 238
• Main Authors: Kameta, Kosei, Kouchi, Noriyuki, Ukai, Masatoshi, Hatano, Yoshihiko
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2002
• Subjects: Alkane; Neutral-dissociation cross section; Photoabsorption cross section; Photoionization cross section; Superexcited state; Synchrotron radiation; Vacuum ultraviolet range; Photoionization cross section; Neutral-dissociation cross section; Photoabsorption cross section; Alkane; Superexcited state; Vacuum ultraviolet range; Synchrotron radiation
• ISSN: 0368-2048; 1873-2526
• DOI: 10.1016/S0368-2048(02)00022-1

The absolute photoabsorption cross sections, σ t, of CH 4 and n-C 4H 10 have been measured in the photon energy range of the valence electrons using a double ionization chamber equipped with a metallic thin film window and synchrotron radiation as a continuous-wavelength light source. The absolute photoionization quantum yields, η, of CH 4 have been also measured, from which the photoionization cross sections, σ i, and neutral-dissociation cross sections, σ d, are obtained. The values of σ t and η of C 1–C 4 normal alkanes including our previous results for C 2H 6 and C 3H 8 have been compared in detail with those by the dipole-simulation method using the virtual photons. The gross features of the σ t and η values of these alkanes are discussed in terms of those as functions of the photon energy and the number of C atoms in an alkane molecule.