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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
Nonadditive interactions in ns2 and spin-polarized ns metal atom trimers
Jacek Kłos1, Piotr S Zuchowski, Łukasz Rajchel
1Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
Abstract:
The origins of nonadditivity in the following groups of metal trimers are examined: alkali earth metals of the IIA group (Be, Mg, and Ca), Zn as a transition metal analog of this group, spin-polarized alkali metals from IA group (Li, Na, K), and the spin-polarized Cu as its transition metal analog. The nonadditive interactions in these trimers are analyzed using the following hierarchy of approximations: the Heitler-London, self-consistent field (SCF), and correlated levels of theory. The exchange nonadditivity, which is included at the Heitler-London level, constitutes a bulk of nonadditive interactions in these systems in their equilibrium structures. The SCF treatment reveals some unphysical characteristics. At the post-SCF levels of theory the multireference character of the wave function increases from atom to dimer to trimer. The role of configurations involving excitations ns-np increases in this sequence and it is the genuine nonadditive effect. There is also a dramatic change in the characteristics of the excited states upon formation of clusters. We use the parameters of these excited states to predict which complexes are bound by the unusually strong nonadditive interactions and which are not.
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