Ion Mobility Measurements and Ion Chemical Reaction Studies at Heavy Elements in a Buffer Gas Cell

Abstract

Drift time measurements of ions in a buffer gas cell filled with argon have been performed from which changes of the ion mobility and ionic radii for various heavy elements and their compounds were determined. The ionic radius of americium shrinks by (3.1 $\pm$ 1.3)% with respect to that of plutonium, and an increase of the radius by (28 $\pm$ 2)% of plutonium oxide with respect to plutonium was found. Ion chemical reactions of erbium ions were studied online in an argon buffer gas cell to which the reaction gases oxygen (O$_2$) and methane (CH$_4$) were added. The erbium ions were implanted into the buffer gas cell with an energy of 50 MeV. The online measured reaction constant $k_{Er+O2}$ = (3.2 $\pm$ 0.4) $\cdot$ 10$^{-10}$ cm$^3$/(molecule $\cdot$ s) for the reaction Er$^{+}$ + O$_{2}$ $\rightarrow$ ErO$^{+}$ + O agrees with a reference measurement $k_{Er+O2}^{FT}$ = (3.6 $\pm$ 0.4)$\cdot$ 10$^{-10}$ cm$^3$/(molecule $\cdot$ s), performed with a Fourier-Transform-Mass-Spectrometer.