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Title: Effect of van der Waals interactions on the structural and binding properties of GaSe

Abstract

The influence of van der Waals interactions on the lattice parameters, band structure, elastic moduli and binding energy of layered GaSe compound has been studied using projector-augmented wave method within density functional theory. We employed the conventional local/semilocal exchange-correlation functionals and recently developed van der Waals functionals which are able to describe dispersion forces. It is found that application of van der Waals density functionals allows to substantially increase the accuracy of calculations of the lattice constants a and c and interlayer distance in GaSe at ambient conditions and under hydrostatic pressure. The pressure dependences of the a-parameter, Ga–Ga, Ga–Se bond lengths and Ga–Ga–Se bond angle are characterized by a relatively low curvature, while c(p) has a distinct downward bowing due to nonlinear shrinking of the interlayer spacing. From the calculated binding energy curves we deduce the interlayer binding energy of GaSe, which is found to be in the range 0.172–0.197 eV/layer (14.2–16.2 meV/Å{sup 2}). - Highlights: • Effects of van der Waals interactions are analyzed using advanced density functionals. • Calculations with vdW-corrected functionals closely agree with experiment. • Interlayer binding energy of GaSe is estimated to be 14.2–16.2 meV/Å{sup 2}.

Authors:
 [1];  [1];  [2];  [3]
  1. Tomsk State University, Lenin Avenue 36, 634050 Tomsk (Russian Federation)
  2. (Russian Federation)
  3. Kemerovo State University, Krasnaya 6, 650043 Kemerovo (Russian Federation)
Publication Date:
OSTI Identifier:
22573962
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 232; Other Information: Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ACCURACY; BINDING ENERGY; BOND ANGLE; BOND LENGTHS; CRYSTAL STRUCTURE; CRYSTALS; DENSITY; DENSITY FUNCTIONAL METHOD; DISPERSIONS; GALLIUM SELENIDES; INTERACTIONS; LATTICE PARAMETERS; LAYERS; MEV RANGE; PRESSURE DEPENDENCE; SEMICONDUCTOR MATERIALS; VAN DER WAALS FORCES

Citation Formats

Sarkisov, Sergey Y., E-mail: sarkisov@mail.tsu.ru, Kosobutsky, Alexey V., E-mail: kosobutsky@kemsu.ru, Kemerovo State University, Krasnaya 6, 650043 Kemerovo, and Shandakov, Sergey D.. Effect of van der Waals interactions on the structural and binding properties of GaSe. United States: N. p., 2015. Web. doi:10.1016/J.JSSC.2015.09.002.
Sarkisov, Sergey Y., E-mail: sarkisov@mail.tsu.ru, Kosobutsky, Alexey V., E-mail: kosobutsky@kemsu.ru, Kemerovo State University, Krasnaya 6, 650043 Kemerovo, & Shandakov, Sergey D.. Effect of van der Waals interactions on the structural and binding properties of GaSe. United States. doi:10.1016/J.JSSC.2015.09.002.
Sarkisov, Sergey Y., E-mail: sarkisov@mail.tsu.ru, Kosobutsky, Alexey V., E-mail: kosobutsky@kemsu.ru, Kemerovo State University, Krasnaya 6, 650043 Kemerovo, and Shandakov, Sergey D.. 2015. "Effect of van der Waals interactions on the structural and binding properties of GaSe". United States. doi:10.1016/J.JSSC.2015.09.002.
@article{osti_22573962,
title = {Effect of van der Waals interactions on the structural and binding properties of GaSe},
author = {Sarkisov, Sergey Y., E-mail: sarkisov@mail.tsu.ru and Kosobutsky, Alexey V., E-mail: kosobutsky@kemsu.ru and Kemerovo State University, Krasnaya 6, 650043 Kemerovo and Shandakov, Sergey D.},
abstractNote = {The influence of van der Waals interactions on the lattice parameters, band structure, elastic moduli and binding energy of layered GaSe compound has been studied using projector-augmented wave method within density functional theory. We employed the conventional local/semilocal exchange-correlation functionals and recently developed van der Waals functionals which are able to describe dispersion forces. It is found that application of van der Waals density functionals allows to substantially increase the accuracy of calculations of the lattice constants a and c and interlayer distance in GaSe at ambient conditions and under hydrostatic pressure. The pressure dependences of the a-parameter, Ga–Ga, Ga–Se bond lengths and Ga–Ga–Se bond angle are characterized by a relatively low curvature, while c(p) has a distinct downward bowing due to nonlinear shrinking of the interlayer spacing. From the calculated binding energy curves we deduce the interlayer binding energy of GaSe, which is found to be in the range 0.172–0.197 eV/layer (14.2–16.2 meV/Å{sup 2}). - Highlights: • Effects of van der Waals interactions are analyzed using advanced density functionals. • Calculations with vdW-corrected functionals closely agree with experiment. • Interlayer binding energy of GaSe is estimated to be 14.2–16.2 meV/Å{sup 2}.},
doi = {10.1016/J.JSSC.2015.09.002},
journal = {Journal of Solid State Chemistry},
number = ,
volume = 232,
place = {United States},
year = 2015,
month =
}
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