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The mobilities of the singly clustered ions of Li+ with constituent gases have been measured with a conventional drift tube over the E/N range 8–89 Td in N2, 10–25 Td in O2, 10–139 Td in CO, 50–348 Td in CO2, and 40–80 Td in CH4. Two methods were employed to determine the mobilities; one was a difference method and the other was based on the pressure dependence of apparent mobilities. It is found that the mobilities of each cluster ion species remain constant over most of the E/N range used and the zero-field values are 1.87±0.07 for Li+(N2)–N2 at 303 K, 1.89±0.11 for Li+(O2)–O2 at 303 K, 1.70±0.06 for Li+(CO)–CO at 303 K, 0.92±0.04 for Li+(CO2)–CO2 at 303 K, and 2.22±0.08 cm2/V s for Li+(CH4)–CH4 at 302 K, respectively. The zero-field mobilities of these polyatomic ions considerably deviate from the values of the Langevin polarization limit. They are predicted with moderate accuracy by assuming a hard sphere-r-4 potential which takes a repulsive core size into account. [ABSTRACT FROM AUTHOR]

The transport coefficients for Li+ ions in some moleculars gases have been measured over a wide range of E/N with a conventional drift tube at temperatures close to 300 K. The zero-field reduced mobilities are found to be 3.91±0.11, 4.44±0.12, 3.64±0.10, 2.46±0.07, and 3.44±0.10 cm2/V s in N2, O2, CO, CO2, and CH4 gas, respectively, and these values except in O2 gas significantly deviate from the Langevin limit. In N2, CO, and CO2 gas, the resulting mobility curves show clear minima at intermediate E/N, but the depressions in O2 and CH4 gas are slight. The drop of the zero-field values in N2, CO, and CO2 gas is explained in terms of an effective ion–quadrupole interaction which provides the r-6 attractive behavior. From the mobility calculations with using n-4–6(γ) potential, it is suggested that the depression of the mobility curve is developed by the addition of a sufficient r-6 term and is partly attributed to inelastic collisions as expected even at intermediate E/N. The experimental diffusion data are compared with the values derived from the generalized Einstein relation. For all systems, the agreement is quite good at intermediate E/N, but there are large discrepancies at other E/N. The sources of the deviation are considered to be clustering reactions and inelastic collisions at low and high field, respectively. [ABSTRACT FROM AUTHOR]

Ion mobility measurements were made for Li+ in Ne and in N2 and Na+ in SF6 using a variable-temperature drift tube. The measurements were made by two different methods: variable-E/N method at constant T and variable-T method at constant E/N, where E, N, and T are the electric field strength, the gas number density, and the gas temperature, respectively. Two datasets were compared at the same effective temperature Teff, as calculated from the Wannier equation. For Li+ in Ne, the two datasets are put on a single curve in the range 150 K

In a drift-tube study, four simple formulas, based on a dynamic equilibrium analysis of two gaseous ion swarms, are proposed to determine simultaneously the forward and reverse reaction frequencies together with two drift velocities. The formulas are put to the test for (N+4,N+2)/N2 system with two arrival time spectra (ATS) generated from the experimental data previously reported at E/N=150 Td (the ratio of electric field strength to gas number density: 1 Td=10-17 V cm2). The percent differences between the data and the determined values are estimated to be 0.8%, -1.4%, 6.8%, and 4.9%, for the drift velocities of N+4 and N+2 ions and the forward and reverse reaction frequencies, respectively. For the same system, two experimental ATS obtained at 180 Td by McKnight et al., being supposedly in near equilibrium, are directly examined by this method. [ABSTRACT FROM AUTHOR]

In a drift-tube analysis, an asymptotic solution for the transport of inter-reacting multiple ion swarms approaching to dynamic equilibrium is proposed. The solution describes a set of similar Gaussian profiles with two common ‘‘equilibrium’’ transport coefficients. Although all the profiles apparently aggregate to the same location, there exists a slight peak difference between arbitrary two spectra. The difference holds even in the equilibrium. A generalized equilibrium constant is defined by the quotient of two reaction-frequency determinants. Those four kinetic constants are uniquely determined from the kinetic coefficients of all ion species without any influence of the initial conditions. The discrepancy between the thermal equilibrium and dynamic equilibrium is briefly discussed. [ABSTRACT FROM AUTHOR]

Deals with the measurement of the mobilities of Li[sup+] ions in gaseous HCl, HBr and HI as a function of the energy parameter E/N at room temperature. Calculated mobilities of Li[sup+] ions in HCl, HBr and HI.