NAMD-note

Namd2-gpu  +p20  conf  >  log

charm_run ++nodelist nodelist namd_2 +p80 ++ppn 20 ../../../ante/allff3/complex_popc/namd/prod_test3/prod8.conf > ../../../ante/allff3/complex_popc/namd/prod_test3/prod8.log &

Minimize’Configuration file:

可调参数:

amber              on

parmfile           ../complex_0.1.prmtop

ambercoor          ../prod1.rst7

#structure          mypsf.psf

#coordinates        mypdb.pdb

#outputName         myoutput

set temperature    300               ;#结构优化时设置没用,但是得有个  

set  outputname        ./prod_2       

firsttimestep      0  

# Continuing a job from the restart files

if {0} {                           ;#最小化用不到输入文件,所以设置为不启用

set inputname      proding_2

binCoordinates     $inputname.restart.coor

binVelocities      $inputname.restart.vel  ;# remove the "temperature" entry if you use this!

extendedSystem    $inputname.xsc

}

模拟参数:

# Input

#paraTypeCharmm      on

#parameters          par_all27_prot_lipid.inp

# NOTE: Do not set the initial velocity temperature if you

# have also specified a .vel restart file!

temperature       $temperature     #跟温度控制没毛线关系,只是用来替代vel,告诉系统刚开始原子的速度是多少

outputname   $outputname            ;#输出的文件都是以这个开头

# Periodic Boundary conditions

# NOTE: Do not set the periodic cell basis if you have also

# specified an .xsc restart file!

if {1} {

cellBasisVector1   311.0  0    0     ;#单元基向量

cellBasisVector2     0  364.0  0

cellBasisVector3     0    0  150.0

cellOrigin      144.5627136230 171.1880187988 76.0607299804

}

wrapAll             on

#PME (for full-system periodic electrostatics)

if {1} {

PME                 yes

PMEGridSpacing      1.0

#manual grid definition

 PMEGridSizeX        312

 PMEGridSizeY        365

 PMEGridSizeZ        152             ;#这三个数需要比周期性稍大一点,且能被2、3、5整除(最小公倍数)

}

# Force-Field Parameters

exclude             scaled1-4         ;#说明哪一种原子-原子相互作用可以忽略

1-4scaling          0.833333         ;#说明弱化的程度,取值为0-1

scnb                2

cutoff              10.0

switching           off              ;#设定是否使用过度函数……见下图

switchdist          10.0

pairlistdist        13.5

# Integrator Parameters

timestep            2.0  ;# 2fs/step

rigidBonds          all  ;# needed for 2fs steps   ;#设定所有与氢相连的键为刚性的不震动的。用了rigidbonds,就把与氢原子相连的化学键的键长固定在平衡值附近了,因为timestep的选取是和体系的振动频率有关,而氢的振动频率最快,因此,加上rigidbond就降低了振动频率,所以才能用2fs,如果不用rigidbond,则2fs的步长太大,用0.5fs比较合适。例外,在溶液中模拟一般用2fs,在真空中一般用0.5fs,也就是不用rigidbond。

rigidTolerance      0.00001

nonbondedFreq       1           ;#设定隔多长时间计算一次总体静电相互作用

fullElectFrequency  2 

stepspercycle       20

# Constant Temperature Control

langevin            on    ;# do langevin dynamics

langevinDamping     1     ;# damping coefficient (gamma) of 5/ps

langevinTemp        $temperature

langevinHydrogen    no    ;# don't couple langevin bath to hydrogens

# Constant Pressure Control (variable volume)

if {0} {

useGroupPressure      yes ;# needed for 2fs steps

useFlexibleCell       yes ;# no for water box, yes for membrane

useConstantArea       yes ;# no for water box, yes for membrane

####上面的是设置系统压力的类型,下面的是设置控压方法,压力应该有,控压方法不一定有(只有平衡时才用控压)。。。温度设置也是一样的()

langevinPiston        on

langevinPistonTarget  1.01325 ;#  in bar -> 1 atm

langevinPistonPeriod  100.0

langevinPistonDecay   50.0

langevinPistonTemp    $temperature

restartfreq         500     ;# 500steps = every 1ps

dcdfreq             500

xstFreq             500   

 

outputEnergies      100

outputPressure      100

# Fixed Atoms Constraint (set PDB beta-column to 1)

#if {0} {

#fixedAtoms          on

#fixedAtomsFile      myfixedatoms.pdb

#fixedAtomsCol       B

#}

# IMD Settings (can view sim in VMD)

#if {0} {

#IMDon           on

#IMDport         3000    ;# port number (enter it in VMD)

#IMDfreq         1       ;# send every 1 frame

#IMDwait         no      ;# wait for VMD to connect before running?

#}

附加参数:

 

执行脚本:

# prodion

#if {0} {

#minimize            100

#reinitvels          $temperature

#}

minimize     1000 ;# 100ps

################################################################################################

Heating’configuration file:

可调参数:

amber              on

parmfile           ../../complex_0.1.prmtop

ambercoor          ../../prod1.rst7

#structure          mypsf.psf

#coordinates        mypdb.pdb

#outputName         myoutput

set temperature    300

outputname         ./prod_3

firsttimestep      0

# Continuing a job from the restart files

if {1} {                                 ;#用到上一步的输出文件

set inputname      prod_2

binCoordinates     ../$inputname.restart.coor

binVelocities      ../$inputname.restart.vel  ;# remove the "temperature" entry if you use this!

extendedSystem    ../$inputname.restart.xsc

}

模拟参数:

# Input

#paraTypeCharmm      on

#parameters          par_all27_prot_lipid.inp

# NOTE: Do not set the initial velocity temperature if you

# have also specified a .vel restart file!

#temperature       $temperature

# Periodic Boundary conditions

# NOTE: Do not set the periodic cell basis if you have also

# specified an .xsc restart file!

if {0} {

cellBasisVector1   311.0  0    0        

cellBasisVector2     0  364.0  0

cellBasisVector3     0    0  150.0

cellOrigin      144.5627136230 171.1880187988 76.0607299804

}

wrapAll             on

# Force-Field Parameters

exclude             scaled1-4

1-4scaling          0.833333

scnb                2

cutoff              10.0

switching           off

switchdist          10.0

pairlistdist        13.5

# Integrator Parameters

timestep            2.0  ;# 2fs/step

rigidBonds          all  ;# needed for 2fs steps

rigidTolerance      0.00001

nonbondedFreq       1

fullElectFrequency  2 

stepspercycle       20

#PME (for full-system periodic electrostatics)

if {1} {

PME                 yes

PMEGridSpacing      1.0

#manual grid definition

 PMEGridSizeX        312

 PMEGridSizeY        365

 PMEGridSizeZ        152

}

# Constant Temperature Control

langevin            on    ;# do langevin dynamics

langevinDamping     1     ;# damping coefficient (gamma) of 5/ps

langevinTemp        $temperature

langevinHydrogen    no    ;# don't couple langevin bath to hydrogens

# Constant Pressure Control (variable volume)

if {0} {

useGroupPressure      yes ;# needed for 2fs steps

useFlexibleCell       yes ;# no for water box, yes for membrane

useConstantArea       yes ;# no for water box, yes for membrane

langevinPiston        on

langevinPistonTarget  1.01325 ;#  in bar -> 1 atm

langevinPistonPeriod  100.0

langevinPistonDecay   50.0

langevinPistonTemp    $temperature

}

restartfreq         1000     ;# 500steps = every 1ps

dcdfreq             3000

xstFreq             3000

outputEnergies      100

outputPressure      100

# Fixed Atoms Constraint (set PDB beta-column to 1)

#if {0} {

#fixedAtoms          on

#fixedAtomsFile      myfixedatoms.pdb

#fixedAtomsCol       B

#}

# IMD Settings (can view sim in VMD)

#if {0} {

#IMDon           on

#IMDport         3000    ;# port number (enter it in VMD)

#IMDfreq         1       ;# send every 1 frame

#IMDwait         no      ;# wait for VMD to connect before running?

#}

附加参数:

reassignFreq 100

reassignTemp 0

reassignIncr 0.1

reassignHold 310          #每隔100步升高0.1k,最终升到310k

执行脚本:

# prodion

#if {0} {

#minimize            100

reinitvels          $temperature

#}

#minimize     1000 ;# 100ps

Run       310000

run           1000000

knowledge

 

1、namd压力控制

压力控制需要周期性边界条件,通过调整unit cell的尺寸和所有原子的坐标(除了固定原子)控制压力。

压力的单位为bar。PRESSURE是根据单个原子计算的压力,GPRESSURE是将氢原子合并到他们相连的重原子上。TEMPAVG、PRESSAVG、GPRESSAVG是之前输出能量的平均值。第一步中,他们是与TEMP、PRESSURE、GPRESSURE相同的。

 

原文地址:https://www.cnblogs.com/jszd/p/11178789.html