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Aufsatz
Collision systems
(1984)
Various approximations which are possible for the theoretical description of colliding ion-atom systems are reviewed. With the emphasis on relativistic influences, a few comparisons of experimental results with relativistic calculations are made.
Aufsatz
Ions of the superheavy elements in vacuum and in solution
(1976)
The extension of the Periodic Table into the range of unknown atomic numbers of above
one hundred requires relativistic calculations. The results of the latter are used to indicate probable values for X-ray transition lines which will be useful for identification of the atomic species formed
during collision between accelerated ions and the target. If the half-lives of the isotopes are long, then the chemistry of these new species becomes an important question which is reviewed for E110, E 111
and E112.
The ...
Aufsatz
A clear atomic example for the surface sensitivity of penning ionization
(1990)
Using a crossed-beam apparatus with a double hemispherical electron spectrometer,
we have studied the spectrum of electrons released in thermal energy ionizing collisions of metastable
He^*(2^3S) atoms with ground state Yb(4f^14 6s^2 ^1S_0) atoms, thereby providing the first Penning electron spectrum of an atomic target with-4f-electrons. In contrast to the HeI (58.4nm) and NeI (73.6/74.4nm)
photoelectron spectra of Yb, which show mainly 4f- and 6s-electron emission in about a 5:1 ratio, the He^*(2^3S) Penning ...
Aufsatz
Self-consistent relativistic molecular calculations of superheavy molecules: (_110 X)F_6
(1978)
Using new relativistic molecular calculations within the Dirac-Slater scheme it is now
feasible to study theoretically molecules containing superheavy elements. This opens a
new era for the prediction of the physics and chemistry of superheavy elements. As an
example we present the results for (_110 X) F_6, where it is shown that relativistic effects are nearly of the same order of magnitude as the crystal-field splitting.
Aufsatz
Beam-foil-excited auger transitions in neon
(1975)
Energy spectra of electrons ejected from collisions between a carbon foil and Ne
projectiles with energies between 1.4 and 20 MeV have been measured. Continuous and
discrete electron energy distributions are observed. Auger transitions of foil-excited Ne have been studied. Using relativistic Dirac-Fock multiconfiguration calculations, most of the measured Auger transitions have been identified.
Aufsatz
Electronic structure of UF_5
(1979)
Non-relativistic and relativistic self-consistent Hartree- Fock-Slater and Dirac-Slater models have been used to calculate one-electron energy levels and ionization energies for UF_5. The calculations were performed in an assumed structure of C_4v symmetry with the uranium atom at the center of mass of the molecule. The spacing and level ordering are compared
with earlier results obtained with the MS X\alpha method using the muffin-tin approximation. Connections with the multiphoton isotope separation scheme of UF_6 ...
Aufsatz
The continuation of the periodic table up to Z = 172.
(1970)
The chemical elements up to Z = 172 are calculated with a relativistic Hartree-Fock-Slater
program taking into account the effect of the extended nucleus. Predictions of the binding energies, the X-ray spectra and the number of electrons inside the nuclei are given for the inner electron shells.
The predicted chemical behaviour will be discussed for a11 elements between Z = 104-120 and compared with previous known extrapolations. For the elements Z = 121-172 predictions of their chemistry and a proposal for the ...