Ab-Initio Approach to the Many-Electron Problem

The method of increments is a wavefunction-based ab initio correlation method for solids, which explicitly calculates the many-body wavefunction of the system. After a Hartree-Fock treatment of the infinite system the correlation energy of the solid is expanded in terms of localised orbitals or of a group of localised orbitals. The method of increments has been applied to a great variety of materials with a band gap, but in this paper the extension to metals is described. The application to solid mercury is presented, where we achieve very good agreement of the calculated ground-state properties with the experimental data.

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Understanding the physical origin of negative capacitance (NC) in High-k oxides: Experimental and ab-initio approach

Chemical Physics Letters ◽

10.1016/j.cplett.2021.138964 ◽

2021 ◽

pp. 138964

Author(s):

O. Khaldi ◽

F. Jomni

Keyword(s):

Ab Initio ◽

Negative Capacitance ◽

Physical Origin ◽

High K ◽

Ab Initio Approach

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Structure and Raman scattering of chained carbon films on copper substrate: ab initio approach

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/292/1/012102 ◽

2018 ◽

Vol 292 ◽

pp. 012102 ◽

Cited By ~ 1

Author(s):

E A Buntov ◽

A F Zatsepin ◽

M B Guseva ◽

D A Boqizoda ◽

B L Oksengendler

Keyword(s):

Raman Scattering ◽

Ab Initio ◽

Copper Substrate ◽

Carbon Films ◽

Ab Initio Approach

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Simulation of Local Surface Modification in STM by ab initio Quantum Chemistry

Surface Review and Letters ◽

10.1142/s0218625x98000864 ◽

1998 ◽

Vol 05 (02) ◽

pp. 493-499 ◽

Cited By ~ 1

Author(s):

V. S. Gurin

Keyword(s):

Surface Modification ◽

Ab Initio ◽

Physical Nature ◽

Atomic Scale ◽

Level Shift ◽

Electrical Field ◽

High Electrical Field ◽

Wide Range ◽

Energy Level Shift ◽

Ab Initio Approach

Surface modification by means of STM has became a well-known method for the artificial formation of nanometer and atomic scale structures. The physical nature of surface modification can consist in a wide range of phenomena (from mechanical indentation up to specific tip-induced chemistry). The high electrical field at the STM tip is considered to be the main feature of STM modification experiments. The field strength is comparable with intramolecular ones and can influence the chemical bonding in surface structures. The model of STM-stimulated modification is considered using the quantum-chemical ab initio approach for a surface cluster in the high electrical field. The destabilization effect, energy level shift, and bond polarization under the STM tip field occur and can show the atomistic nature of surface transformations in STM.

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