CHARGE-TRANSFER REACTIONS BETWEEN XENON IONS AND IRON ATOMS IN AN ARGON-XENON INDUCTIVELY-COUPLED PLASMA

Xenon is added to the axial channel of an argon inductively coupled pl asma (ICP) at doses up to 1.5% of the aerosol gas flow. Emission is co llected from the gas flowing into the sampling orifice of a mass spect rometer (MS). These Xe doses have little effect on the electron densit y n(e) or on the intensities of Fe (I) emission lines. Certain Fe (II) lines are enhanced when Xe is added, particularly those from Fe+ stat es that can be populated by near-resonant charge transfer between Xeand neutral Fe. Calculations based on measured values of n(e) indicate that Xe+ should be present at densities of up to 7 x 10(14) cm(-3), w hich should be sufficient Xe+ to drive the proposed charge transfer re actions.