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标题: 在mdp中deform设置拉伸膜后如何分析膜的力学性能？ [打印本页]

作者
Author: herbrex 时间: 2024-3-7 10:10
标题: 在mdp中deform设置拉伸膜后如何分析膜的力学性能？
我的体系是真空中一个PS薄膜，之前通过各位指点采用deform设置，在x方向上对盒子进行延长进而减小压强，起到对film拉伸的目的，目前已经得到了我想要的结果，但是我需要对拉伸这个过程中film的力学性能进行表征，比如这一过程中film受到的应力是多少，怎么计算的？各位大佬有无相关的方法或文献？谢谢指点！
附上我的mdp参数以及拉伸前后的gro文件
mdp：
title    = OPLS  MD simulation
; Run parameters
integrator  = md       ; leap-frog integrator
nsteps    = 25000000 ; 2 * 25000000 = 50000000 fs (50 ns)
dt       = 0.002    ; 2 fs
; Output control
nstxout          = 50000    ; save coordinates every 500 ps
nstvout          = 50000    ; save velocities
nstenergy          = 50000    ; save energies
nstlog             = 50000    ; update log file
nstxout-compressed  = 50000    ; save compressed coordinates
                              ; nstxout-compressed replaces nstxtcout;
compressed-x-grps = System ; replaces xtc-grps
; Bond parameters
continuation          = no    ; Restarting after NPT
constraint_algorithm = lincs    ; holonomic constraints
constraints          = h-bonds ; h-bonds constrained
lincs_iter             = 1       ; accuracy of LINCS
lincs_order          = 4       ; also related to accuracy
; Neighborsearching
cutoff-scheme = Verlet
ns_type       = grid    ; search neighboring grid cells
nstlist       = 10       ; 20 fs, largely irrelevant with Verlet scheme
rcoulomb       = 1.2    ; short-range electrostatic cutoff (in nm)
rvdw          = 1.2    ; short-range van der Waals cutoff (in nm)
; Electrostatics
coulombtype    = PME    ; Particle Mesh Ewald for long-range electrostatics
pme_order    = 4       ; cubic interpolation
fourierspacing  = 0.16    ; grid spacing for FFT
; Temperature coupling is off
tcoupl    = no          ; modified Berendsen thermostat
tc-grps    = System ; three coupling groups - more accurate
tau_t    = 0.1          ; time constant, in ps
ref_t    = 300          ; reference temperature, one for each group, in K
; Pressure coupling is on
pcoupl             = berendsen    ; Pressure coupling on in NPT
pcoupltype       = semiisotropic
tau_p             = 4.0                ; time constant, in ps
ref_p             = 1.0    1.0       ; reference pressure, in bar
compressibility    = 0    4.5e-5          ; isothermal compressibility of water, bar^-1
deform=0.01 0 0 0 0 0
; Periodic boundary conditions
pbc    = xyz    ; 3-D PBC
; Dispersion correction
DispCorr = EnerPres  ; account for cut-off vdW scheme
; Velocity generation
gen_vel    = yes    ; assign velocities from Maxwell distribution
gen_temp = 300    ; temperature for Maxwell distribution
gen_seed = -1       ; generate a random seed

作者
Author: chunaizhanshi 时间: 2025-9-19 11:24
请问解决了吗，我也被困扰很久

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