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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
Chemical and physical properties of superheavy elements
(1976)
A knowledge of the physical and chemical properties of superheavy elements is
expected to be of great value for the detection of these elements, owing to the
need for chemical separation in their isolation and identification. The methods
for predicting their electronic structures, expected trends in their chemical and
physical properties and the results of such predictions for the individual superheavy
elements are reviewed. The periodic table is extended up to element 172.
Aufsatz
X-Ray spectra of superheavy and quasi-superheavy elements
(1973)
We discuss the possibility of identifying superheavy elements from the observation
of their M-shell x-ray spectra, which might occur during the collision of a superheavy element with a heavy target. The same question is discussed for the possible observation of the x-rays from the quasimolecule (quasi-superheavy element) which is formed during such a heavy-ion collision. It is shown that it is very difficult, if not impossible, to determine any information about the interesting quantum electrodynamical effects from ...
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
Relativistic effects in physics and chemistry of element 105. [Part] III.
(American Institute of Physics, 1992)
Electronic structures of MOCl_3 and MOBr_3 molecules, where M = V, Nb, Ta, Pa, and element 105, hahnium, have been calculated using the relativistic Dirac-Slater discrete variational method. The character of bonding has been analyzed using the Mulliken population analysis of the molecular orbitals. It was shown that hahnium oxytrihalides have similar properties to oxytrihalides of Nb and Ta and that hahnium has the highest tendency to form double bond with oxygen. Some peculiarities in the electronic structure of ...
Aufsatz
Slave-boson approach to the size-dependent transition from van der Waals to covalent bonding in Hg_n clusters
(1994)
We use a microscopic theory to describe the dynamics of the valence electrons in divalent-metal clusters. The theory is based on a many-body model Harniltonian H which takes into account, on the same electronic level, the van der Waals and the covalent bonding. In order to study the ground-state properties of H we have developed an extended slave-boson method. We have studied the bonding character and the degree of electronic delocalization in Hg_n clusters as a function of cluster size. Results show that, for ...
Aufsatz
Theory for the change of bond character in divalent-metal clusters
(1991)
To determine the size dependence of the bonding in divalent-metal clusters we use a many-electron Hamiltonian describing the interplay between van der Waals (vdW) and covalent interactions. Using a saddle-point slave-boson method and taking into account the size-dependent screening of charge fluctuations, we obtain for Hg_n a sharp transition from vdW to covalent bonding for increasing n. We show also, by solving the model Hamiltonian exactly, that for divalent metals vdW and covalent bonding coexist already in the dimers.