Low-Field Drift Velocities and Reactions of Nitrogen Ions in Nitrogen

Abstract

Drift velocities and reactions of nitrogen ions have been investigated at 300°K at values of E/N (the ratios of electric field to number density) between 1.5 and 20X10"" 16 V cm 2 , and at pressures between 0.5 and 1 Torr. Ions were produced in a glow discharge and were gated into a drift cell, withdrawn through a slit, and their mass and intensity were determined as a function of the drift time by a mass analyzer. Comparison of experimental results with theoretical calculations allowed the determination of true drift velocities and reaction rates for ions undergoing reaction during the drift time. The ions in nitrogen were found to occur in two groups, N 2 + -N4 + and N + -N3 + , such that interactions within the groups are much faster than any interactions between the groups. Rate constants for the reaction N 2 + +N 2 +N 2 -> N4 + +N 2 were found to vary from 7X10~2 9 to 2X10" 29 cm 6 /sec between E/N of 5X10" 16 and 18X10" 16 V cm 2 , while for the reverse reaction the rates varied from 0.3X10 -13 to 110X10 -13 cm 3 /sec. The pressure dependences of the reaction rates were consistent with a three-body forward reaction and a two-body reverse reaction over our limited pressure range. For the N + -N3 + system, the interaction of N + with the neutral gas to produce N 3 + was observed at E/N =5X10~1 6 V cm 2 with a rate constant of 3X10~2 9 cm 6 /sec. No reactions could be positively identified which produced N + over the range of our experimental parameters.

Searching for ways to create energetic materials based on polynitrogen compounds (review)

“…The first theoretical studies were devoted to the properties of the van der Waals complex (N 2 ) 2 [19,20]. In addition, much effort has been devoted to studying the N + 4 cation [21,22], which was earlier detected experimentally in an electric discharge [23]. It is assumed that N + 4 can be a precursor of the N 4 neutral compound, which is of great practical interest.…”

Mathematical analysis of reactive ion transport in dynamic equilibrium: The case of two ionic species

“…As far as the reaction rates of N,+ and N,+ are concerned, however, controversy still remains regarding their accuracy. So in this analysis we adopted the transport coefficients determined by McDaniel and co-workers and the reaction rates determined by McKnight et al (5). Several useful ion-current profiles for the (N,+, N4+)/N2 system were obtained by McKnight et al ( 3 , from which we find that the dynamic balance develops at E / N = 150 Td (1 Td = lo-'' V cm2).…”

“…Note that only the first terms in [5] and [61 will dominate the dynamical behavior of two ion swarms, because exp(A,t) decreases much faster than exp(A,t). The resulting coefficients are listed below:…”

“…T I and T 2 are expressed as where DZi and Dri are longitudinal and transverse diffusion coefficients of ith species, respectively. By applying the expansion technique in [5] and [6], we can derive an explicit form of the solutions as follows:…”

A Mass-Selective Variable-Temperature Drift Tube Ion Mobility-Mass Spectrometer for Temperature Dependent Ion Mobility Studies

“…H ybrid ion mobility-mass spectrometers (IM-MS) based on drift tubes coupled to orthogonal time-of-flight mass spectrometers (TOF) were first introduced over 40 y ago [1,2]; however, the analytical utility of these types of instruments was not fully realized for several decades. A resurgence of interest in the IM-MS technique evolved from work by Bowers and coworkers [3] and Jarrold [4,5], and by Clemmer and Jarrold [6].…”