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Aufsatz
Relativistic Dirac-Fock-Slater program to calculate potential-energy curves for diatomic molecules
(1986)
A LCAO-MO (linear combination of atomic orbitals - molecular orbitals) relativistic Dirac-Fock-Slater program is presented, which allows one to calculate accurate total energies for diatomic molecules.
Numerical atomic Dirac-Fock-Slater wave functions are used as basis functions. All integrations as well as the solution of the Poisson equation are done fully numerical, with a relative accuracy of 10{^-5} - 10{^-6}. The details of the method as well as first results are presented here.
Aufsatz
Relativistic calculations of atomic structure
(1984)
A review of relativistic atomic structure calculations is given with a emphasis on the Multiconfigurational-Dirac-Fock method. Its problems and deficiencies are discussed together with the contributions which go
beyond the Dirac-Fock procedure.
Aufsatz
Test for basis-set errors in relativistic Dirac-Fock-Slater calculations with a numerical AO-DFS-basis
(1987)
A fully relativistic four-component Dirac-Fock-Slater program for diatomics,
with numerically given AO's as basis functions is presented. We discuss the problem of the errors due to the finite basis-set, and due to the influence of the negative energy solutions of the Dirac Hamiltonian. The negative continuum contributions are found to be very small.
Aufsatz
Comparison between experiment and theory in heavy electronic systems
(Gräff, G. (Hrsg.), 1981)
Aufsatz
Relativistic many-electron SCF correlation diagram for Pb-Pb
(Fabian, Derek J. (Hrsg.), 1981)
Aufsatz
Hyperfine structure and isotopic shift of the n^2 P_J levels (n = 7-10) of ^203,205 TI measured by Doppler-free two-photon spectroscopy
(1988)
Using Doppler-free two-photon absorption spectroscopy, we have measured hyperfine splitting constants as well as isotopic level shifts of the 6s^2 np ^2 P_l/2,3/2 states in (n=7-10) in ^203 TI and ^205 TI.
Calculations for hyperfine constants and electron density at the nucleus have been performed by the Dirac-Fock method. The experimental results are compared with these calculations as well as with
the predictions of the semiempirical theory.
Aufsatz
Ground state correlation energy of the Be-sequence for Z = 4-20 in MCDF approximation
(1989)
The ground state (J = 0) electronic correlation energy of the 4-electron Be-sequence is calculated in the Multi-Configuration Dirac-Fock approximation for Z = 4-20. The 4 electrons were distributed over the configurations arising from the 1s, 2s, 2p, 3s, 3p and 3d orbitals. Theoretical values obtained here are in good agreement with experimental correlation energies.
Aufsatz
Estimation of the ground state correlation energy for isoelectronic series of 2 to 20 electrons
(1987)
Correlation energies for all isoelectronic sequences of 2 to 20 electrons and Z = 2 to 25 are obtained by taking differences between theoretical total energies of Dirac-Fock calculations and experimental total energies. These are pure relativistic correlation energies because relativistic and QED effects are already taken care of. The theoretical as well as the experimental values are analysed critically in order to get values as accurate as possible. The correlation energies obtained show an essentially consistent ...
Aufsatz
Relativistic atomic level calculations with nuclei carrying additional fractional charges
(1983)
One-electron energy levels and wavelengths have been calculated for Na-like ions whose nuclei carry quarks with additional charges ±e/3, ±2e/3. The calculations are based on relativistic self-consistent field procedures. The deviations from experimental values exhibit regularities which allow an extrapolation for the wavelengths of 3s - 3p, 3s - 4p, 3p - 3d, and 3p - 4s transitions for the nuclear charge Z = 11± 1/3, ±2/3. A number of transitions are found in the region of visible light which could be used in an ...