Electron attachment and electron impact ionization of SF/sub 6/ and SF/sub 6//Ar clusters

Journal Article · Wed Jun 01 04:00:00 EDT 1988 · J. Chem. Phys.; (United States)

OSTI ID:5161334

Stamatovic, A; Scheier, P; Maerk, T D

Electron attachment and electron impact ionization of SF/sub 6/ and SF/sub 6/Ar clusters have been investigated in a molecular beamelectron impact ion sourcemass spectrometer system. Positive ion mass spectra of neat SF/sub 6/ clusters contain ((SF/sub 6/)/sub n/xSF/sub x/)/sup +/ fragment ion series with 0less than or equal toxless than or equal to5 and in addition ((SF/sub 6/)/sub n/S/sub 2/F/sub 5/)/sup +/ ions which have to be formed via international ion molecule reactions. Positive ion mass spectra of mixed SF/sub 6/Ar clusters include ion series of nonstoichiometric fragment ions (SF/sub 5/xAr/sub n/)/sup +/, (SF/sub 6/xSF/sub 5/xAr/sub n/)/sup +/, ((SF/sub 6/)/sub 2/xSF/sub 5/xAr/sub n/)/sup +/, and, in addition, stoichiometric ions comprised of (SF/sub 6/xAr/sub n/)/sup +/ and ((SF/sub 6/)/sub 2/Ar/sub n/)/sup +/. These stoichiometric ions are only present with ngreater than or equal to3. Electron attachment to neat SF/sub 6/ clusters gives rise only to stoichiometric (SF/sub 6/)/sup -//sub n/ ions, whereas attachment to mixed SF/sub 6/Ar clusters yields ion series consisting of (Ar/sub n/SF/sub 6/)/sup -/, (Ar/sub n/(SF/sub 6/)/sub 2/)/sup -/, and (Ar/sub n/x(SF/sub 6/)/sub 3/)/sup -/. This indicates that the dissociative channel into SF/sup -//sub 5/ present in the monomer is efficiently quenched in case of clusters. The negative ion mass spectra show in contrast to the positive ion mass spectra a strong dependence on electron energy due to a strong resonance of the attachment cross sections near zero electron energy

• Research Organization: Institut fuer Ionenphysik, Leopold Franzens Universitaet, Technikerstr. 25, A 6020 Innsbruck, Austria
• OSTI ID: 5161334
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 88:11; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ARGON COMPLEXES
COLLISIONS
COMPLEXES
ELECTRON ATTACHMENT
ELECTRON COLLISIONS
ELECTRON-MOLECULE COLLISIONS
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
IONIZATION
MASS SPECTROSCOPY
MOLECULE COLLISIONS
SPECTROSCOPY
SULFUR COMPOUNDS
SULFUR FLUORIDES