Torsion and Bending PBC in MD++

Torsion and Bending PBC in MD++

Seunghwa Ryu and Wei Cai

This tutorial describes how Torsion/Bending Periodic Boundary Conditions (t-PBC and b-PBC) are implemented in MD++. We provide several MD++ script files and describe how to use them in detail. The theoretical background is published in

Torsion and Bending Periodic Boundary Conditions for Modelling the Intrinsic Strength of Nanowires, Journal of Mechanics and Physics of Solids, 56, 3242, (2008). (PDF)

Compile executable file

First, you need to install MD++ on your computer by following the instructions on MD++ Manuals. You will also need the cookies directory (not in the standard MD++ distribution), where additional source files such as md_torsion.cpp are located.

To turn on the t-PBC and b-PBC utility, modify src/Makefile so that

 TOB = yes

In this tutorial, we will use gold nanowire (modelled by the EAM potential) as an example. We can compile the executable file (e.g. on mc-cc.stanford.edu) by

 make eam build=R SYS=mc-cc