Observation of the formation of N sup + and ArN sup + in the collisions of Ar sup + ( sup 2 P sub 3/2,1/2 ) with N sub 2

Journal Article · Thu Mar 01 00:00:00 EST 1990 · Journal of Chemical Physics; (USA)

DOI:https://doi.org/10.1063/1.457934· OSTI ID:6985578

Flesch, G D; Ng, C Y ^[1]

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1. Ames Laboratory, U. S. Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011 (US)

Absolute total cross sections for the reactions, Ar{sup +}({sup 2}{ital P}{sub 3/2,1/2})+N{sub 2}{r arrow}N{sup +}+N+Ar (reaction (1)) and ArN{sup +}+N (reaction (2)), have been measured in the center-of-mass collision energy ({ital E}{sub c.m.}) range of 6.2--123.5 eV. The appearance energy for the formation of N{sup +} ({ital E}{sub c.m.}=8.65{plus minus}0.21 eV) is in agreement with the thermochemical threshold for reaction (1). The comparison of the collision energy dependence of the N{sup +} cross section with the photoionization efficiency spectrum of N{sup +} from N{sub 2} suggests that the predissociative multielectron states of N{sup +}{sub 2}, {tilde {ital C}} {sup 2}{Sigma}{sup +}{sub {ital u}}, {tilde {ital F}} {sup 2}{Sigma}{sup +}{sub {ital g}}, {tilde {ital G}} {sup 2}{Sigma}{sup +}{sub {ital g}}, and {sup 2}{Sigma}{sup +}{sub {ital g}} (2{sigma}{sub {ital g}}){sup {minus}1}, which are responsible for the dissociative photoionization of N{sub 2}, also play a role in the formation of N{sup +} via reaction (1). Product ArN{sup +} ions of reaction (2) are only observed in the {ital E}{sub c.m.} range of 8.2--41.2 eV. At {ital E}{sub c.m.} slightly above the thermochemical thresholds of reactions (1) and (2), the majority of ArN{sup +} and N{sup +} ions are scattered backward and forward with respect to the center-of-mass velocity of reactant Ar{sup +}, respectively. This observation is rationalized by a charge transfer predissociation mechanism which involves the formation of ArN{sup +} and N{sup +} ions via nearly collinear Ar{sup +}-N-N collision configurations at {ital E}{sub c.m.} near the thresholds of reactions (1) and (2). At {ital E}{sub c.m.}{ge}11 eV, more than 92% of the charge transfer product N{sup +}{sub 2} ions are found to be slow ions formed mostly by the long-range electron jump mechanism.

• OSTI ID: 6985578
• Journal Information: Journal of Chemical Physics; (USA), Vol. 92:5; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ARGON IONS
CHEMICAL REACTION KINETICS
ARGON NITRIDES
CHEMICAL REACTION YIELD
NITROGEN
ATOMIC IONS
CHARGE EXCHANGE
ION-ATOM COLLISIONS
ION-MOLECULE COLLISIONS
MOLECULAR IONS
TOTAL CROSS SECTIONS
ARGON COMPOUNDS
ATOM COLLISIONS
CHARGED PARTICLES
COLLISIONS
CROSS SECTIONS
ELEMENTS
ION COLLISIONS
IONS
KINETICS
MOLECULE COLLISIONS
NITRIDES
NITROGEN COMPOUNDS
NONMETALS
PNICTIDES
RARE GAS COMPOUNDS
REACTION KINETICS
YIELDS
400201* - Chemical & Physicochemical Properties