Mobility of Cl− ions in Xe gas and the Cl−–Xe interaction potential

The mobility of Cl− ions in Xe gas at 300 °K has been measured in a drift tube mass spectrometer for a wide range of values of the ionic energy parameter E/N (the ratio of the electric field strength to the neutral gas number density). A Cl−–Xe interaction potential is assumed and a kinetic theory appropriate for the ion motion is used to derive the mobility from the potential. Then an iterative technique is used to modify the potential so as to fit the predicted mobility to the experimental data. This interaction potential is directly determined by the experimental data for a range of internuclear separation distances from about 4 to about 10 a.u. At distances greater than 10 a.u., the potential is the induced dipole polarization potential.