Tensile

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%reload_ext lammpscn.lammps

%reload_ext lammpscn.lammps

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%%lmp_script
# ref: https://doi.org/10.1080/08927022.2017.1313418
# setup problem
units           real
atom_style      atomic
boundary        p p p
dimension    3
boundary     p p p

lattice      fcc 5.3919 orient x 1 0 0 orient y 0 1 0 orient z 0 0 1
region       box prism 0 5 0 5 0 5 0 0 0 
create_box   1 box 
create_atoms 1 box
mass         1 1.0
 
# system contains only atoms 
pair_style      lj/cut     12.00000
pair_coeff      1  1   0.238067 3.405

# use LB combination rules
pair_modify    mix arithmetic
 
pair_modify    shift no
pair_modify    tail yes
 
# cutoff list width, in Ang. (from rc_lj)
neighbor            1.200000 bin
 
# list update, check every timestep after 5 steps
neigh_modify    every 1 delay 5 check yes
 
# groups definition
group Argon.dat type      1
 
# compute thermo info 'a la Newton' to compare
# with td.out values (same units)
variable natoms       equal atoms
variable t
# variable nt_eb        equal ebond/v_natoms*4.184
# variable nt_epl       equal eangle/v_natoms*4.184
# variable nt_etor      equal (edihed+eimp)/v_natoms*4.184
# variable nt_LJ        equal (evdwl-etail)/v_natoms*4.184
# variable nt_ES        equal (ecoul+elong)/v_natoms*4.184
# variable nt_Ep        equal pe/v_natoms*4.184
# variable nt_E         equal etotal/v_natoms*4.184
# variable nt_Pat       equal press*1.01325
# variable nt_rho       equal density*1000.
# variable nt_V         equal vol
# variable nt_T         equal temp
 
variable initstep   equal  step
variable nstep      equal  1000
variable perthermo  equal  100
variable pertraj    equal  100000
variable perpdb     equal  v_nstep+1
# nstep must be a multiple of nevery
variable nevery     equal  10
variable nrepeat    equal  v_nstep/v_nevery
variable nfreq      equal  v_nstep+v_initstep
variable finalstep  equal  v_initstep+v_nstep

# print thermo info variable values
thermo ${perthermo}

timestep 1.0
 
# NVE run 
#fix 1 all nve
#run ${nstep}
 
# NPT triclinic
fix 1 all npt  temp  60.00  60.00 100  tri 0.986923  0.986923  1000.0 tchain 10  pchain 10  mtk yes tloop 4 ploop 4
run ${nstep}

%%lmp_script # ref: https://doi.org/10.1080/08927022.2017.1313418 # setup problem units real atom_style atomic boundary p p p dimension 3 boundary p p p lattice fcc 5.3919 orient x 1 0 0 orient y 0 1 0 orient z 0 0 1 region box prism 0 5 0 5 0 5 0 0 0 create_box 1 box create_atoms 1 box mass 1 1.0 # system contains only atoms pair_style lj/cut 12.00000 pair_coeff 1 1 0.238067 3.405 # use LB combination rules pair_modify mix arithmetic pair_modify shift no pair_modify tail yes # cutoff list width, in Ang. (from rc_lj) neighbor 1.200000 bin # list update, check every timestep after 5 steps neigh_modify every 1 delay 5 check yes # groups definition group Argon.dat type 1 # compute thermo info 'a la Newton' to compare # with td.out values (same units) variable natoms equal atoms variable t # variable nt_eb equal ebond/v_natoms*4.184 # variable nt_epl equal eangle/v_natoms*4.184 # variable nt_etor equal (edihed+eimp)/v_natoms*4.184 # variable nt_LJ equal (evdwl-etail)/v_natoms*4.184 # variable nt_ES equal (ecoul+elong)/v_natoms*4.184 # variable nt_Ep equal pe/v_natoms*4.184 # variable nt_E equal etotal/v_natoms*4.184 # variable nt_Pat equal press*1.01325 # variable nt_rho equal density*1000. # variable nt_V equal vol # variable nt_T equal temp variable initstep equal step variable nstep equal 1000 variable perthermo equal 100 variable pertraj equal 100000 variable perpdb equal v_nstep+1 # nstep must be a multiple of nevery variable nevery equal 10 variable nrepeat equal v_nstep/v_nevery variable nfreq equal v_nstep+v_initstep variable finalstep equal v_initstep+v_nstep # print thermo info variable values thermo ${perthermo} timestep 1.0 # NVE run #fix 1 all nve #run ${nstep} # NPT triclinic fix 1 all npt temp 60.00 60.00 100 tri 0.986923 0.986923 1000.0 tchain 10 pchain 10 mtk yes tloop 4 ploop 4 run ${nstep}

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%%lmp_script
print           "Deformation X-direction" 
variable        tmp equal "lx"
variable        L0 equal ${tmp}
variable        strain equal "(lx - v_L0)/v_L0"
variable        p1 equal "v_strain"
fix             1 all npt temp ${tkrun} ${tkrun} 100 y 0 0 100 z 0 0 100
fix             2 all deform 1 x erate ${def_rate} units box remap v
fix             def1 all print ${sdt} "${p1} ${p2} ${p3} ${p4} ${p5} ${p6} ${p7} ${p8} ${p9} ${p10} ${p11} ${p12} ${p13} ${tk}" file cdefx_${tkrun}K.txt screen no title "#Strain     -Pxx [MPa]   -Pyy [MPa]     -Pzz [MPa]     -Pyz [MPa]   -Pxz [MPa]     -Pxy [MPa]    lxx [A]    lyy [A]    lzz [A]   ayz [A]    axz [A]    axy [A]   T [K]  ;  "
dump            mydump all atom ${sdtdp} cdefx_${tkrun}K.lammpstrj
reset_timestep  0
run             400000
write_data      cdefx_${tkrun}K.data

%%lmp_script print "Deformation X-direction" variable tmp equal "lx" variable L0 equal ${tmp} variable strain equal "(lx - v_L0)/v_L0" variable p1 equal "v_strain" fix 1 all npt temp ${tkrun} ${tkrun} 100 y 0 0 100 z 0 0 100 fix 2 all deform 1 x erate ${def_rate} units box remap v fix def1 all print ${sdt} "${p1} ${p2} ${p3} ${p4} ${p5} ${p6} ${p7} ${p8} ${p9} ${p10} ${p11} ${p12} ${p13} ${tk}" file cdefx_${tkrun}K.txt screen no title "#Strain -Pxx [MPa] -Pyy [MPa] -Pzz [MPa] -Pyz [MPa] -Pxz [MPa] -Pxy [MPa] lxx [A] lyy [A] lzz [A] ayz [A] axz [A] axy [A] T [K] ; " dump mydump all atom ${sdtdp} cdefx_${tkrun}K.lammpstrj reset_timestep 0 run 400000 write_data cdefx_${tkrun}K.data

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最后更新: November 14, 2023

Authors: Roy Kid