Dear Colleagues
Currently I’m working on variants of Tersoff potential in LAMMPS packeage, but I found few things that is not obvious to me.
For reference, a part of SiCGe.tersoff is written below;
C Si(D) Si(D) 3.0 1.0 0.0 3.8049e4 4.3484 -0.57058 0.72751 1.5724e-7 1.97205 395.1451 2.3573 0.1527 2.9839 1597.3111
C Si(D) C 3.0 1.0 0.0 3.8049e4 4.3484 -0.57058 0.72751 0.0 0.0 0.0 1.95 0.15 0.0 0.0
C C Si(D) 3.0 1.0 0.0 3.8049e4 4.3484 -0.57058 0.72751 0.0 0.0 0.0 2.3573 0.1527 0.0 0.0
- What is m and gamma in the parameters? I couldn’t figure out its usage in Pair_tersoff.cpp source file, According to the file, m has to be either 1 or 3, but is there any physical interpretation?
- Are 3 elements (ex.C Si(D) Si(D)) corresponds to i,j,k in Tersoff poetential each?
- if so, (question #2) why C-Si(D)-C has parameters with zero values while C-Si(D)-Si(D) is not (actually, in latter case, parameters are following the rules on paper by Tersoff,1989)? According to these zeros, The energy of the former is calculated to be zero, which is weird.
I would really appreciate any comments on these subjects.
Thanks in advance.
--------------------------------------------------------------------Hayoung Chung.
SSnD Lab, Seoul National University
summeryoung88@…24…