# bilinear stress strain behavior

first off, please *always* copy the mailing list on your replies and
don't reply to individual people only.

i have a bead spring model for which need a linear harmonic potential( in
bond_style potential) ( i.e linear stress-strain behavior) upto strain 0.08
with young's modulus 5 gpa (max. stress at 0.1 strain =0.4gpa) and then
another linear harmonic potential till strain 0.45 with with young's modulus
0.54 gpa (max. stress at 0.45 strain =0.6gpa) then stress drops to 0 at
strain = 0.45..i.e a cutoff at this strain value.

again, you fail to describe where specifically you have questions
about how LAMMPS works or how to use a specific feature. you are just
stating some things.

science is not a game of jeopardy, where you can simply provide the
answers and somebody else will formulate the question for you.

whether a linear harmonic potential can even describe the behavior
that you want and which specific parameters you need, is something
that *you* will have to figure out. this is a general force field
issue and not a question about LAMMPS in the first place.

axel.

hello

Is there a way to superimpose two potentials between two atoms using bond style in lammps

hello

Is there a way to superimpose two potentials between two atoms using bond
style in lammps

you can use a tabulated bond style or define a bond multiple times.

sir
does that mean if i define bond 1 between atoms m and n then i can also define bond 2 between atoms m and n? can i superimpose same potential for defining both the bonds( 1 and 2)?

how to tabulate the table in lammps (bond style table )???

Or use bond_style hybrid.

Steve

hello sir
how to do continuous energy minimization as loading is increased with suppose time step of 55 fs.After energy minimization and relaxation of initial structure ,loading is applied by displacing a thin layer of particles at the end of the system with strain rate of 7.558 x 10^-8 per integration step. model is a box with lower layer fixed and upper layer is given a constant strain rate.

please understand that this mailing list is not a service that
translates chunks of a paper into LAMMPS input script commands.
therefore please *you* have to explain *first*, how you expect this to
happen, what commands you have looked at and tried and where exactly
your problem is. LAMMPS comes with many case study examples and howto
discussions, and while there may not be an immediate solution for your
specific problem among them, they may serve as inspiration or template
for developing a simulation strategy. many people here that do respond
to questions, consider requests like the one above with no indication
of giving this any thought or making some experiments, irritating if
not offensive.

axel.