Electron stimulated desorption of anions and cations from condensed allyl glycidyl ether

Abstract

We report measurements of the electron stimulated desorption (ESD) of anions and cations from thin films of allyl glycidyl ether (AGE), formed by condensation onto multilayer Kr and Pt substrates using a high sensitivity time of flight mass analyser. Measurements were performed as a function of film thickness, incident electron energy (E(i)) and effective incident current. Below incident electron energies of 20 eV the desorption of anions is dominated by the process of dissociative electron attachment (DEA) via several transient negative ions at E(i) between 5.5 and 16.5 eV. Comparisons between measurements for AGE and ethyl oxirane show that the ESD of anions is essentially that of the glycidyl (epoxide) ring, though DEA occurring at the ether, within the linear part of the AGE molecule is also observed. Cation yields are dominated by the desorption of small fragments formed via scission of the same ether bond.

Non-thermal ion desorption from an acetonitrile (CH3CN) astrophysical ice analogue studied by electron stimulated ion desorption

“…3, the relative ion yield dependence of CH 3 CNH + on the electron beam current exhibits almost a quadratic growth. Such nonlinear dependence has already been observed for low energy electron-stimulated anion desorption, 54 fs-laser induced associative desorption 55 and ion desorption following ultra-short XUV laser pulses, 56,57 indicating that collisions and/or reactions between more than one dissociating products may lead to a more complex desorption framework. In this sense, this scenario may be consistent with the framework of proton-transfer reactions between dissociating species during ion desorption as the first step towards the production of more complex species, such as cluster ions.…”

“…3). Based on the similar results of Yildirim, 54 this tendency suggests that ion collisions are necessary to induce proton-transfer reactions on the CH 3 CN ice top surface.…”

Radial electron fluence around ion tracks as a new physical parameter for the detection threshold of PADC using Geant4-DNA toolkit

“…(II) The electrons with energies less than 7.4 eV, which is the cut-off energy in the simulations, can also act to cleave the chemical bonds by processes such as dissociative electron attachment, and could cause breaks in PADC (Bazin et al, 2009;Böhler et al, 2013;Alizadeh et al, 2016;Yildirim et al, 2010). We should thus consider the interactions of such low energy electrons in order to more accurately determine secondary electron histories and the density of such electrons around the ion's trajectory.…”