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lammps 简单模型弛豫时周期边界出问题。 已有2人参与
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问题：利用lammps建立一个矩形，x和y方向为周期，z方向为非周期，(p p m) ,利用NVT弛豫（300K），发现周期边界处的原子混乱; 如果把(p p m) 改为(p m m)，发现还是周期边界方向出现混乱，如下图。不知什么原因？谢谢！ lammps脚本 #initialize units metal boundary p p m atom_style atomic #============================================================================ # difinition of variable #============================================================================ variable T0 equal 300 #K variable dis equal 15 variable edge equal 20 variable h equal $r+3+${dis} variable subup equal 0 variable subdw equal -20 variable fixedline equal ${subdw}*0.75 variable bxl equal -${r}-${edge} variable bxr equal ${r}+${edge} variable byl equal -${r}-${edge} variable byr equal ${r}+${edge} variable bzl equal ${subdw}-${edge} variable bzr equal $h+$r+${edge} #============================================================================ # build group #============================================================================ region box block ${bxl} ${bxr} ${byl} ${byr} ${bzl} ${bzr} units box create_box 2 box #box 中原子类型分类有6种 lattice fcc 3.61505 #orient x 1 0 0 orient y 0 1 1 orient z 0 -1 1 region rsubtrate1 block INF INF INF INF ${subdw} ${subup} units box region rsubtrate intersect 2 box rsubtrate1 create_atoms 1 region rsubtrate group gsubtrate region rsubtrate region rsubactive1 block INF INF INF INF ${fixedline} ${subup} units box region rsubactive intersect 2 box rsubactive1 group gsubactive region rsubactive group gsubfixed subtract gsubtrate gsubactive set group gsubfixed type 2 pair_style eam/alloy pair_coeff * * CuAg.eam.alloy Cu Cu #============================================================================ # setting #============================================================================ timestep 0.001 #fs thermo_style custom step temp etotal ke pe press vol neighbor 0.5 bin neigh_modify every 5 delay 0 check yes #============================================================================ # # initial velocities #============================================================================ thermo 100 velocity all create ${T0} 482748 dist gaussian fix 1 all nvt temp ${T0} ${T0} 0.1 drag 0.2 #保持初始温度，在NVT下弛豫 dump 2 all atom 100 relax_ball.lammpstrj run 800  周期为 p p m  周期为 p m m |
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