Turgut Bastug

Use of the DV Xα-Method in the Field of Superheavy Atoms

Abstract: We are discussing our manner to calculate the total energy for small molecules within the DV-Xα approximation by using only the monopol part of the potential in the solution of the Poisson equation. A discussion of the relativistic effects including our results for heavy diatomic molecules, is followed by remarks on the choice of the exchange-correlation potential together with our results of calculations on molecules for the element 106 their chemical interpretation. We conclude with results on very heavy correlation diagrams for collision systems with a united Z above 110.

ENERGETICS AND STRUCTURAL STABILITY OF LANTHANUM MICROCLUSTERS

Abstract The energetics and the structural stability of lanthanum microclusters (Lan) have been investigated by performing relativistic density functional calculations and molecular dynamics (MD) simulations. An empirical potential energy function has been parameterised for a lanthanum element by using the dimer interaction potential energy profile of La2, which is calculated by relativistic density functional method. Stable structures of the microclusters for n=3–13 have been determined by MD simulation and electronic structures have been calculated by relativistic density functional method. MD simulations have also been performed for spherical clusters with sizes n=19–157.

Molecular-dynamics simulations of uranium microclusters

Structural stability and energetics of uranium microclusters, U n ( n =3–13, 27–137), have been investigated by molecular-dynamics simulations. An empirical model potential energy function has been...

Zirconium microclusters: molecular-dynamics simulations and density functional calculations

Abstract Structural stability and energetics of zirconium microclusters Zrn (n=3–13) have been investigated by molecular-dynamics simulations and density functional calculations. A semi-empirical modelpotential energy function has been parametrized for the zirconium element by using the dimer interaction potential energy profile of Zr2, which is calculated by the relativistic density functional method. Stable structures of the microclusters for n=3–13 have been determined by a molecular-dynamics simulation. Relativistic density functional calculations have been performed for n=3–7. It has been found that zirconium microclusters prefer to form three-dimensional compact structures.

Molecular-dynamics simulations of gold clusters

Structural stability and energetics of gold microclusters Aun (n=313,19–555) have been investigated by molecular-dynamics simulations. A model potential energy function has been parametrized for the gold element by using the dimer interaction potential energy profile of the Au2, which is calculated by relativistic density functional method. Stable structures of the microclusters for (n=3–13) have been determined by a molecular-dynamics simulation. It has been found that gold microclusters prefer to form three-dimensional compact structures. Molecular-dynamics simulations have also been performed for spherical gold clusters generated from fcc crystal structure with sizes (n=19–555 ).

Size dependence in adsorption on model surfaces

Abstract Considering the chemisorption of atomic oxygen on Li(001) surface, the size dependence in adsorption on the model surfaces has been investigated. All-electron density functional calculations within the local density approximation have been applied to cluster models with increasing size. The influence of cluster size on the physics and chemistry of adsorption has been investigated.

Relativistic density functional calculations for potential energy curves of uranyl nitrate hydrate

Abstract Metal - ligand distances of U=O (uranyl oxygen) and U-OH 2 in the uranyl nitrate dihydrate have been optimized, using the all-electron fully relativistic discrete-variational Dirac - Fock - Slater ( DV-DFS ) MO method. The calculated bond length of U=O for a free complex is larger than the experimental value for the crystal and the Uue5f8OH 2 distance was in good agreement with the experimental results.The shape of the potential curves indicates individual strength of the Uue5fbO and Uue5f8OH 2 bonds and reveals that the Uue5fbO bond was stronger.