Dear LAMMPS users and developers,
I thank Dr. Kohlmeyer for his answers to my previous mails and I am sorry that was not unable to explain my problem correctly.
However, please allow me to get back to my objective: I would like to draw phonon dispersion curves and density of states for ionic systems ( such as quartz, langasite and langatate) by using LAMMPS .
Could someone point me towards a tutorial/sample that would explain how to draw such curves for a system including long range coulombic interactions between charged particles such as the Si and O ions of quartz, using only standard LAMMPS fixes (so as to use the long-range summation techniques already implemented in LAMMPS) and possibly a publicly available analysis program?
I already “googled” for that with several combinations of keywords but found mainly pointers to GULP by J.D. Gale which would mean learning how to use still another big code, whereas I would prefer benefiting from my investment in LAMMPS…
Any help will be appreciated.
sincerely yours,
Santunu
Dear LAMMPS users and developers,
I thank Dr. Kohlmeyer for his answers to my previous mails and I am sorry
that was not unable to explain my problem correctly.
However, please allow me to get back to my objective: I would like to draw
phonon dispersion curves and density of states for ionic systems ( such as
quartz, langasite and langatate) by using LAMMPS .
Could someone point me towards a tutorial/sample that would explain how to
draw such curves for a system including long range coulombic interactions
between charged particles such as the Si and O ions of quartz, using only
standard LAMMPS fixes (so as to use the long-range summation techniques
already implemented in LAMMPS) and possibly a publicly available analysis
program?
no. outside of the (external) fix phonon add-on that
you already have come across, there is no integrated
way to do this. if you look up the corresponding
theory and papers, you could also do this manually,
but that can be tedious and error prone.
i am just wondering, why you need to do this for
a (simple?) crystal with a classical potential?
these kind of calculations are more commonly
done with codes using density functional theory
to describe interactions rather than classical potentials.
axel.