TY - JOUR
T1 - A study of the target gas dependence on the collisional ionization mass spectra of some metastable and hypervalent molecules
AU - Gellene, Gregory I.
AU - Porter, Richard F.
N1 - Funding Information:
We are grateful to the National Science Foundation for support through the Materials Science Center (Grant GH-33637), Cornell University and NSF Grants CHE-8215184 and CHE-8314501.
PY - 1985/3/15
Y1 - 1985/3/15
N2 - Collisional ionization mass spectra of a fast beam of neutral molecules with ionization potentials in the range 4-5 eV have been obtained with a series of target gases, NO2, O2, N2 and He. Neutral beams were generated in a near resonant electron transfer process X+ +K(g) → X* + K+ where X+ is He2+, H3+, ND4+ or N2D7+. The efficiency of collisional ionization of metastable He2* and the ground state radicals ND4 and N2D7 on target gas decreases in the order NO2 > O2 > N2 > He. Of the four neutral species studied, only in the case of H3* is a change in rotational state of the projectile required for ionization. This restriction may explain the lack of an apparent target gas dependence on the efficiency of ionizing H3*. The technique is extended to a study of the CD5 radical where no evidence for metastability is observed. An upper limit of 10-8 s is set on the lifetime of this species.
AB - Collisional ionization mass spectra of a fast beam of neutral molecules with ionization potentials in the range 4-5 eV have been obtained with a series of target gases, NO2, O2, N2 and He. Neutral beams were generated in a near resonant electron transfer process X+ +K(g) → X* + K+ where X+ is He2+, H3+, ND4+ or N2D7+. The efficiency of collisional ionization of metastable He2* and the ground state radicals ND4 and N2D7 on target gas decreases in the order NO2 > O2 > N2 > He. Of the four neutral species studied, only in the case of H3* is a change in rotational state of the projectile required for ionization. This restriction may explain the lack of an apparent target gas dependence on the efficiency of ionizing H3*. The technique is extended to a study of the CD5 radical where no evidence for metastability is observed. An upper limit of 10-8 s is set on the lifetime of this species.
UR - http://www.scopus.com/inward/record.url?scp=0040299151&partnerID=8YFLogxK
U2 - 10.1016/0168-1176(85)85036-9
DO - 10.1016/0168-1176(85)85036-9
M3 - Article
AN - SCOPUS:0040299151
SN - 0168-1176
VL - 64
SP - 55
EP - 66
JO - International Journal of Mass Spectrometry and Ion Processes
JF - International Journal of Mass Spectrometry and Ion Processes
IS - 1
ER -