First Determination of the Ionization Potential of Americium and Curium (pages 814–815)
Dipl.-Chem. Rüdiger Deissenberger, Dipl.-Phys. Stefan Köhler, Dr. Friedhelm Ames, Dr. Klaus Eberhardt, Dipl.-Phys. Nicole Erdmann, Dipl.-Chem. Heike Funk, Prof. Dr. Günter Herrmann, Prof. Dr. Heinz-Jürgen Kluge, Dipl.-Phys. Martin Nunnemann, Dr. Gerd Passler, Dr. Joachim Riegel, Dr. Franz Scheerer, Dr. Norbert Trautmann and Dr. Franz-Josef Urban
Article first published online: 22 DEC 2003 | DOI: 10.1002/anie.199508141
By multistep resonance ionization with lasers, followed by mass spectrometry, the first ionization potential of neutral atoms can be measured with quantities of only about one nanogram. The ionization potentials of americium (5.9736(3) eV) and of curium (5.9914(2) eV) were thus determined for the first time. The figure on the right shows a plot of the number of ions N versus the total photon energy Etot of three laser beams, which are essential for the experiment. The arrow points to the ionization threshold.