Gas‐phase ion chemistry in germane–propane and germane–propene mixtures

Abstract

Germane-propane and germane-propene gaseous mixtures were studied by ion trap mass spectrometry. Variations of ion abundances observed under different partial pressure ratios and mechanisms of ion-molecule reactions elucidated by multiple isolation steps are reported. In addition, the rate constants for the main reactions were experimentally determined and compared with the collisional rate constants to obtain the reaction efficiencies. The yield of ions containing both Ge and C atoms is higher in the germane-propene than in the germane-propane system. In the former mixture, chain propagation takes place starting from germane ions reacting with propene and proceeds with the formation of clusters such as Ge(2)C(4)H(n) (+) and Ge(3)CH(n) (+).

Ion chemistry in germane/fluorocompounds gaseous mixtures: a mass spectrometric and theoretical study

“…While the stoichiometry of these solids cannot be directly correlated with the composition of the gaseous phase, the study of the ionic processes involved in the initial polymerisation steps gives valuable hints to optimise the running conditions leading to final materials of the desired composition 22, 23. These considerations have stimulated numerous experimental and theoretical studies by our group on the ion chemistry occurring in binary and ternary mixtures containing GeH 4 , saturated and unsaturated hydrocarbons, and other simple compounds such as O 2 , CO, CO 2 , SiH 4 , NH 3 , and PH 3 24–35. From the fundamental point of view, these studies have also disclosed unexplored features of the reactivity of Ge + , GeH n + ( n ≥ 1), and Ge m H n + ( m > 1, n ≥ 1), as well as many ionic processes involving GeH 4 as a gaseous substrate.…”

Gas-Phase Ion Chemistry of GeH4/B2H6 Mixtures

“…In our laboratory, we have developed a solid method for the study of the gasphase ion chemistry of several mixtures containing silicon and/or germanium hydrides. [22][23][24][25][26][27][28][29][30][31][32][33] Reaction sequences and rate constants have been obtained for a large number of systems, thus yielding valuable information about the experimental conditions leading to the final material. While our interest has been traditionally focused on positive ions, quite recently we have also shifted our attention to the less investigated field of gas-phase negative ions.…”

Negative gas‐phase ion chemistry of GeH4: a quadrupole ion trap study

“…In the past years, our research group has been deeply involved in the study of the gas‐phase ion chemistry of germanium hydrides by different mass spectrometric techniques. Self‐condensation reactions10, 11 and gas‐phase mixtures of germane or methylgermane with hydrides of C and/or N, P were studied in order to obtain information on the early ion clustering reactions that eventually lead to deposition of doped germanium carbides 12–23. Recently, our attention has shifted to negative germane ions, which were observed to give extensive condensation reactions in the relatively high‐pressure environment of a triple quadrupole mass spectrometer 24.…”