https://doi.org/10.1140/epjb/e2008-00366-7
Application of a hybrid quantum mechanics and empirical molecular dynamics multiscale method to carbon nanotubes
1
Department of Physics, Tsinghua University, Beijing, 100084, P.R. China
2
The International Centre for Materials Physics, Chinese Academy of Sciences, Shenyang, 110016, P.R. China
Corresponding author: a zx00@mails.tsinghua.edu.cn
Received:
27
May
2008
Revised:
5
August
2008
Published online:
27
September
2008
We present a hybrid multiscale method for coupling quantum mechanics to empirical molecular dynamics, which is named as hybrid energy density method. In this approach, quantum mechanical treatment is spatially confined to a small region, surrounded by a larger molecular mechanical region. A unified expression of total energy combining quantum mechanical and molecular mechanical descriptions, is given by employing a localized energy and a weight associated with it on each site. And we can perform the dynamical simulations of entire system according to the given total energy. We use the hybrid energy density method to simulate two models of carbon nanotubes (CNT): one is a long CNT with an open end, and the other a long CNT containing a di-vacancy under stretching. Calculations of the two CNT models demonstrate that the hybrid multiscale method is required to accurately treat the local quantum mechanical region with the influence of the larger molecular mechanical region.
PACS: 71.15.Mb – Density functional theory, local density approximation, gradient and other corrections / 61.46.-w – Structure of nanoscale materials / 31.15.xv – Molecular dynamics and other numerical methods
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2008
