Effects of van der Waals Interactions in the Adsorption of Isooctane and Ethanol on Fe(100) Surfaces

被引：65

作者：

Bedolla, Pedro O. ^{[1
,2
]}

Feldbauer, Gregor ^{[1
,2
]}

Wolloch, Michael ^{[1
,2
]}

Eder, Stefan J. ^{[2
]}

Doerr, Nicole ^{[2
]}

Mohn, Peter ^{[1
]}

Redinger, Josef ^{[1
]}

Vernes, Andras ^{[1
,2
]}

机构：

[1] Vienna Univ Technol, Inst Appl Phys, A-1040 Vienna, Austria

[2] AC2T Res GmbH, Austrian Ctr Competence Tribol, A-2700 Wiener Neustadt, Austria

来源：

JOURNAL OF PHYSICAL CHEMISTRY C | 2014年 / 118卷 / 31期

关键词：

DENSITY-FUNCTIONAL THEORY; GENERALIZED GRADIENT APPROXIMATION; INITIO MOLECULAR-DYNAMICS; TOTAL-ENERGY CALCULATIONS; INTERMOLECULAR INTERACTIONS; ULTRASOFT PSEUDOPOTENTIALS; ELECTRON LOCALIZATION; TRANSITION; FORCES;

D O I：

10.1021/jp503829c

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

van der Waals (vdW) forces play a fundamental role in the structure and behavior of diverse systems. Because of development of functionals that include nonlocal correlation, it is possible to study the effects of vdW interactions in systems of industrial and tribological interest. Here we simulated within the framework of density functional theory (DFT) the adsorption of isooctane (2,2,4-trimethyl-pentane) and ethanol on an Fe(100) surface, employing various exchange-correlation functionals to take vdW forces into account. In particular, this paper discusses the effect of vdW forces on the magnitude of adsorption energies, equilibrium geometries, and their role in the binding mechanism. According to our calculations, vdW interactions increase the adsorption energies and reduce the equilibrium distances. Nevertheless, they do not influence the spatial configuration of the adsorbed molecules. Their effect on the electronic density is a nonisotropic, delocalized accumulation of charge between the molecule and the slab. In conclusion, vdW forces are essential for the adsorption of isooctane and ethanol on a bcc Fe(100) surface.

引用

页码：17608 / 17615

页数：8

共 76 条

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