Stability of Porous Carbon Structures Obtained from Reverse Monte Carlo using Tight Binding and Bond Order Hamiltonians

S. K. JAIN; J. FUHR; R. J-M PELLENQ; J. P. PIKUNIC; C. BICHARA; K. E. GUBBINS

STUDIES IN SURFACE SCIENCE AND CATALYSIS

Año: 2005 p. 1 - 8

0167-2991

The constrained Reverse Monte-Carlo (RMC) technique [1,2] was used to generate atomic configurations of disordered microporous carbons in a previous work. However, a carbon structure obtained from RMC is a result of the fitting to some structural data such as obtained from X-ray diffraction; it does not guarantee the stability of the resulting models when a realistic interatomic potential is used. In the present work, we studied the stability of these RMC structures using canonical Monte-Carlo simulations. Two different descriptions of the carbon-carbon and carbon-hydrogen interactions are used, both encompassing the bonding processes characteristic of carbon chemistry. The first approach is based on a bond-order potential while the second considers a tight binding model. We found that the structures obtained from RMC simulations undergo local structural changes upon relaxation, however the porous structure of the models remains intact.