Dissociative photoionization of dimethyl ether in the energy range of 13.3～14.3 eV

doi:10.3969/j.issn.0253-2778.2020.05.010

Abstract

Abstract: Dissociative photodissociation of dimethyl ether in the photon energy of 13.30～14.30 eV was studied using threshold photoelectron photoion coincidence mass spectrometry, combined with photoionization using a vacuum ultraviolet light source from synchrotron radiation. In this range, the dimethyl ether ions in B2B2 and C2A2 states were prepared, and the main fragment ions were m/z=45, 29 and 31. By subtracting the contribution of the m/z=29 fragment ions, the reliable time-of-flight profile of the m/z=31 fragment ions was obtained. Then the related kinetic energy distribution was derived from fitting the profile. Below 14.00 eV, a unique statistical dissociation was observed for the formation of the m/z=31 ions, while the dissociation mechanism was changed significantly to dual dissociation

Key words: threshold photoelectron-photoion coincidence, time-of-flight mass spectroscopy, dissociation dynamics, reaction mechanism

CLC Number:

O643.1

XU Lei, WU Xiangkun, YU Tongpo, ZHOU Xiaoguo, LIU Shilin. Dissociative photoionization of dimethyl ether in the energy range of 13.3～14.3 eV[J]. Journal of University of Science and Technology of China, 2020, 50(5): 629-636.

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