Electron impact single ionization and dissociative excitation of H₃O⁺, HD₂O⁺and D₃O⁺

Abstract

First absolute cross sections for electron impact single ionization of H3O+, HD2O+ and D3O+ and for dissociative excitation (DE) producing H+ and D+ are reported. The animated crossed electron-ion beam method has been employed in the energy range from threshold to 2500 eV. The maxima of these cross sections are found to be unusually small (<1×10-17 cm2). The ionization threshold energies are determined to be 24.7±0.5, 24.4±0.5 and 24.0±0.5 eV for H3O+, HD2O+ and D3O+, respectively. The observed DE threshold energies lie in the range 10-12.5 eV and the maximum kinetic energies released are between 3 and 4 eV. Significant differences are observed between the results obtained for the three isotopomers.

Electron-impact total ionization cross sections of hydrocarbon ions

“…3. A recent experiment on the formation of H 3 O ++ by electron impact [ 8 ] is compared to the present theory in Sec. 3.…”

Kinetic-energy release of fragments from electron-impact dissociation of the molecular hydrogen ion and its isotopologues

“…(15). Hence, integration of the PP KER cross section (23) over E k yieldsσ PP as required for comparison with El Ghazaly et al [18].…”

“…Many experimental measurements of the KER cross sections have been used to extract scattering cross sections [8][9][10][11][12][13][14][15][16][17][18], identify dissociative processes [8][9][10][11][12][13][14][15][16][17][18], and to determine experimental conditions [18][19][20], molecular structure [21,22] and collision dynamics [21]. The KER cross sections can be extracted from a complete close-coupling calculation that includes all degrees of freedom (electronic, vibrational, and rotational).…”

Commission 14: Atomic and Molecular Data: (Donnees Atomiques Et Moleculaires)

“…New data for ionization can be found for H 2 (Kim k Rudd 1999, Celiberto et al 1999, Hanel et al 2002, H 2 0 (Kim k Rudd 1999, Hanel et al 2002, Champion, Hanssen, & Hervieux 2002, CO (Tian k Vidal 1999, Almeida et al 1999, Mangan, Lindsay, k Stebbings 2000, C O j (Deutsch et al 2002), CH 4 (Khare, Sharma, k Tomar 1999), C 2 H 2 (Furuya et al 2000), N j (Deutsch et al 2002), NO (Lindsay et al 2000), N 0 2 (Lindsay et al 2000, Jiao et al 2002, and for dissociative ionization of O j and N j (Siari et al 1999), NH+, N H j , N H j , OH^, and OHj (Djuric et al 2000), CO^ (Bahati et al 2001a), and N j (Bahati et al 2001b). We note that dissociative excitation has been considered for H 2 (Celiberto et al 1999).…”

“…The process of dissociative recombination is an important process in which the electron is captured by a molecular ion resulting in a number of neutral products. It is an efficient process producing complex neutral molecules: H^ (Larson et al 2000, Serov et al 2001, Pichl, Nakamura, k Horacek 2001, HD+ (Amitay et al 1999, Larson et al 2000, Orel 2000, Larson k Orel 2001, IL+ (Jensen et al 2001, Glosfk et al 2001, Strasser et al 2001a, H 2 0+ (Jensen et al 1999), H 3 0+ (Neau et al 2000, Bahati et al 2001c), HCN+ (Sheehan et al 1999, Talbi, LePadellec, k Mitchell 2000, HeJ (Carata, Orel, k Suzor-Weiner 1999), HeH+ (Larson k Orel 1999), LiH+ (Krohn et al 2001), CH+ (Carata et al 2000), C2H+ (Derkatch et al 1999), OH+ (Larson et al 2000), O j (Peverall et al 2001), and NO+ (Mostefaoui et al 1999, Schneider et al 2000, LePadellec et al 2001.…”