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arXiv · 0907.3806

Ab-initio calculation of the effect of stress on the chemical activity of graphene

P. L. de andres·J. A. Verges
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Abstract

Graphene layers are stable, hard, and relatively inert. We study how tensile stress affects $σ$ and $π$ bonds and the resulting change in the chemical activity. Stress affects more strongly $π$ bonds that can become chemically active and bind to adsorbed species more strongly. Upon stretch, single C bonds are activated in a geometry mixing $120^{o}$ and $90^{o}$; an intermediate state between $sp^{2}$ and $sp^{3}$ bonding. We use ab-initio density functional theory to study the adsorption of hydrogen on large clusters and 2D periodic models for graphene. The influence of the exchange-correlation functional on the adsorption energy is discussed.

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P. L. de andres, J. A. Verges. 2009-07-22. Ab-initio calculation of the effect of stress on the chemical activity of graphene. https://doi.org/10.1063/1.3010740

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