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Title: On the theory of adsorption on graphene-like compounds

Abstract

Based on a previously proposed model of the electronic spectrum of binary A{sub N}B{sub 8–N} graphene-like compounds (GLC), adsorption theory is constructed, which allows determination of the role of the adatom level position, the adatom–substrate coupling constant, and the gap inherent to GLC in the free state with heteropolar bonds in the formation of the adatom electronic structure. The cases of free-standing and epitaxial GLCs on a metal surface are considered. In the case of free-standing GLCs, analysis shows local states mainly contribute to the adatom occupation number n{sub a} at large and intermediate adatom–GLC coupling constants; as the coupling constants decrease, the contribution of the GLC valence band increases. The main feature of an epitaxial GLC on metal is the absence of a gap, hence, the contribution of adatom local states to n{sub a}. Estimations show that changes in the adatom–substrate and GLC–metal coupling constants affect n{sub a} in almost the same way. In this case, the dependence of n{sub a} on the GLC gap is not critical from the qualitative viewpoint. Adsorption on the GLC–semiconductor structure is briefly discussed.

Authors:
 [1]
  1. Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation)
Publication Date:
OSTI Identifier:
22649645
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 51; Journal Issue: 2; Other Information: Copyright (c) 2017 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ADSORPTION; CARBON COMPOUNDS; COUPLING CONSTANTS; ELECTRON SPECTRA; ELECTRONIC STRUCTURE; ENERGY GAP; EPITAXY; GRAPHENE; OCCUPATION NUMBER; SEMICONDUCTOR MATERIALS; SUBSTRATES; SURFACES; VALENCE

Citation Formats

Davydov, S. Yu., E-mail: Sergei-Davydov@mail.ru. On the theory of adsorption on graphene-like compounds. United States: N. p., 2017. Web. doi:10.1134/S1063782617020051.
Davydov, S. Yu., E-mail: Sergei-Davydov@mail.ru. On the theory of adsorption on graphene-like compounds. United States. doi:10.1134/S1063782617020051.
Davydov, S. Yu., E-mail: Sergei-Davydov@mail.ru. Wed . "On the theory of adsorption on graphene-like compounds". United States. doi:10.1134/S1063782617020051.
@article{osti_22649645,
title = {On the theory of adsorption on graphene-like compounds},
author = {Davydov, S. Yu., E-mail: Sergei-Davydov@mail.ru},
abstractNote = {Based on a previously proposed model of the electronic spectrum of binary A{sub N}B{sub 8–N} graphene-like compounds (GLC), adsorption theory is constructed, which allows determination of the role of the adatom level position, the adatom–substrate coupling constant, and the gap inherent to GLC in the free state with heteropolar bonds in the formation of the adatom electronic structure. The cases of free-standing and epitaxial GLCs on a metal surface are considered. In the case of free-standing GLCs, analysis shows local states mainly contribute to the adatom occupation number n{sub a} at large and intermediate adatom–GLC coupling constants; as the coupling constants decrease, the contribution of the GLC valence band increases. The main feature of an epitaxial GLC on metal is the absence of a gap, hence, the contribution of adatom local states to n{sub a}. Estimations show that changes in the adatom–substrate and GLC–metal coupling constants affect n{sub a} in almost the same way. In this case, the dependence of n{sub a} on the GLC gap is not critical from the qualitative viewpoint. Adsorption on the GLC–semiconductor structure is briefly discussed.},
doi = {10.1134/S1063782617020051},
journal = {Semiconductors},
number = 2,
volume = 51,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2017},
month = {Wed Feb 15 00:00:00 EST 2017}
}
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