175 research outputs found
Coupling and Dissociation in Artificial Molecules
We show that the spin-and-space unrestricted Hartree-Fock method, in
conjunction with the companion step of the restoration of spin and space
symmetries via Projection Techniques (when such symmetries are broken), is able
to describe the full range of couplings in two-dimensional double quantum dots,
from the strong-coupling regime exhibiting delocalized molecular orbitals to
the weak-coupling and dissociation regimes associated with a Generalized
Valence Bond combination of atomic-type orbitals localized on the individual
dots. The weak-coupling regime is always accompanied by an antiferromagnetic
ordering of the spins of the individual dots. The cases of dihydrogen (H,
) and dilithium (Li, ) quantum dot molecules are discussed in
detail.Comment: 7 pages. Latex with 4 GIF and 1 EPS figures. Based on an invited talk
at the ISSPIC10 conference (see http://www.physics.gatech.edu/isspic10/) A
version of the manuscript with high quality figures incorporated in the text
is available at http://calcite.physics.gatech.edu/~costas/qds_isspic10.html
For related papers, see http://www.prism.gatech.edu/~ph274c
Comment on "Density functional theory study of some structural and energetic properties of small lithium clusters" [J. Chem. Phys. 105, 9933 (1996)]
The Ionization Potentials of small Li_N clusters are calculated with a Shell
Correction Method. They are used to illustrate that, within the jellium
approximation, deformed cluster shapes provide an adequate description of the
observed systematic size dependence of the properties of simple metal clusters.
Such deformation effects were overlooked in the analysis of Gardet et al.Comment: Latex/Revtex, 2 pages with 1 Postscript figur
The structure and reactivity of heterogenous surfaces and study of the geometry of surface complexes
Issued as Progress report, and Statement of costs report, Project no. G-41-674 (continued by G-41-687 and continues G-41-664
The structure and reactivity of heterogeneous surfaces and study of the geometry of surface complexes
Issued as Progress report, Project no. G-41-667 (continues G-41-653
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