Mobilities and longitudinal diffusion coefficients for K+ ions in nitrogen and argon

Abstract

We have constructed a drift tube with a movable ion source and measured the mobilities and longitudinal diffusion coefficients for K+ ions at 303 °K in N2 and at 305 °K in Ar in the pressure range 0.3–5.0 Torr, over the E/N range 4–346 Td in N2 and 3–320 Td in Ar. The zero-field reduced mobilities for K+ ions in N2 and Ar were determined to be 2.50±0.03 and 2.63±0.03 cm2/V sec, respectively. Both values are in excellent agreement with the values reported by Elford and Milloy. When our data are compared with the values obtained by Thomson et al. in N2 and the values obtained by James et al. in Ar over the entire E/N range, we find that the mean deviations are about 1.7%, independent of gas species and E/N. Our zero-field reduced mobilities are about 1.2% lower in both cases than the values compiled by Ellis et al. It is concluded that the discrepancy is due to a systematic error and is not caused by clustering reactions. The mean values of NDL over the E/N range 4–7 Td in N2 and 5–10 Td in Ar were found to be 1.96×1018 and 2.09×1018 cm−1 sec−1, respectively. Both values are about 7% higher than the values calculated from our mobility data by the generalized Einstein relation and from the same parameters reported by Pai et al.

The Mobility of K+ Ions in Helium and Argon

“…The present results agree with those of Milloy and Robson (1973) to within O· 5% and Elford and Milloy (1974} (not shown) to within 0·2% except at 0·0724 kPa where the present results are O· 7% higher at low values of E/N. The results of Takebe et al (1980) agree with the present results to within approximately O· 5% for E/N> 30 Td but at low values of E/N they fall below these data. The results of Skullerud (1973) agree with the present results to within the error limits but do not extend to low enough values of E/N to determine the values of the zero field reduced mobility accurately.…”

The Mobility of Li + Ions in Helium and Argon

“…291 4·68 Keller et al (1973) 319 4·57±0·12 Akridge et at. (1975) 300 4·63±0·09 Takata (1977) 306±3 4·76±0·17 Kaneko et al (1978) 4·5 ±0·09 Takebe et al (1982) 304 4·56±0·05 Present work 294 4·66±0·02…”

“…Previous determinations of KO for Li + in Ar are listed in Akridge et al (1975); open triangles, Takata (1977); and closed triangles, Takebe et al (1982). Tyndall (1938) .…”

Spectroscopy of K+⋅Rg and transport coefficients of K+ in Rg (Rg=He–Rn)

“…47 with good precision at all E/N, much better than any other potential. The agreement is particularly striking at low E/N.…”