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 · Wed Feb 28 23:00:00 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), Journal Name: Journal of Chemical Physics; (USA) Vol. 92:5; ISSN JCPSA; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

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