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ZEKE-PFI (zero kinetic energy pulsed field ionization) photoelectron spectra of the Na(H 2 0), Na(D 2 0), Na(NH 3 ), and Na(ND 3 ) complexes are reported. Spectra of all four complexes were obtained by single-photon ionization, and, for the Na(NH 3 ) and Na(ND 3 ) complexes, by two-color (I+ I') photoionization as well, with the A 2 E state serving as the intermediate resonance. Improved values for the ionization energies (IE) and intermolecular vibrational frequencies of the complexes were determined. The single-photon ZEKE-PFI spectra show transitions only between states of the same vibrational symmetry, in accord with the selection rule for allowed electronic transitions. Some of the two-color ZEKE-PFI spectra, however, show strong transitions between states of different vibrational symmetry which we attribute to vibronic coupling in the intermediate state.

Measured single-photon zero-kinetic-energy pulsed field ionization ͑ZEKE-PFI͒ photoelectron spectra of the sodium-water complex are presented and compared with the results of rotationally resolved ab initio calculations. The very nonatomiclike behavior of the photoionization of this Na͑H 2 O͒ complex is essential in accounting for several significant features in these spectra. Agreement between the calculated and measured photoelectron spectra is encouraging. Furthermore, these results suggest that combined experimental and theoretical studies of ZEKE-PFI spectra can be very useful in elucidating the molecular structure and intermolecular force fields of small clusters.

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Time-and space-resolved electron density measurements, made both above the load coil and in the load coil region of a pulsed inductively coupled plasma, are presented. These data, coupled with argon and calcium emission data, give values for the rates of both radial and vertical transport in the plasma. The data indicate that analyte emission behavior is governed primarily by the rate at which the central channel can be heated through radial transport processes. The electron densities measured in the load coil region agree well with electron densities calculated by models assuming local thermodynamic equilibrium, but agree poorly with non-equilibrium models. Some of the timedependent emission behavior observed in previous work with modulated plasmas is explained by non-uniform heating of argon in the load coil region.