ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
Field ionization has been employed as a new technique to determine the ionization potential of an impurity doped in a nonpolar fluid. This has been shown for a model system, CH3I doped into argon for argon densities ranging from the gas up to the triple point liquid. The ionization potential in the medium reflects the different possible configurations of the medium atoms around the dopant at the moment of excitation and, therefore, is given by a distribution. This distribution is identified with that of the polarization energy between the positive ion and the medium. The first and second moments of the polarization distribution were calculated at the densities at which the experiments were performed. Simulated spectra (generated using the experimental results obtained in pure CH3I, the calculated moments, and a Gaussian shape for the polarization distribution) reproduce closely the experimental ionization potential. Furthermore, by combining the experimental data with the calculated distributions, we obtained the density dependence of the quasi-free electron energy in argon. These results are consistent with previous experimental data and with recent theoretical calculations. © 1995 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.470136
