用lammps做模拟时想用lj单位
势函数用lj/cut
pair_style lj/cut rc
pair_coeff 1 2 ε* σ*
参数用Ar的相关参数: ε=115.5K σ=3.4nm
请问转换到 lj 单位,这俩数应该是多少呢,转换公式是什么?
还有就是算出来的能量是负的,这正常吗?负能量代表什么含义呢?
in文件:
units lj
dimension 3
boundary p p p
atom_style atomic
neighbor 0.2 bin
neigh_modify every 1 delay 0 check yes
read_data Model.data
pair_style lj/cut 3.5
pair_coeff * * 0.507 0.76
group bead1 type 1
group bead2 type 2
fix FREEZE all setforce 0.0 0.0 0.0
fix 1 all nve
compute overlap bead1 group/group bead2
thermo 100
thermo_style custom step c_overlap
thermo_modify norm no
timestep 0.001
dump 1 all custom 100 overlap_total.xyz id type x y z
run 1000
计算结果:
Step c_overlap
0 -0.76528644
100 -0.76528644
200 -0.76528644
300 -0.76528644
400 -0.76528644
500 -0.76528644
600 -0.76528644
700 -0.76528644
800 -0.76528644
900 -0.76528644
1000 -0.76528644
Loop time of 0.0147074 on 1 procs for 1000 steps with 129 atoms