[gmx-users] NPT MD Run Problem
teklebrh at ualberta.ca
teklebrh at ualberta.ca
Thu Mar 11 19:15:49 CET 2010
Dear Gromacs users,
I have equilibration my system using the position restraint NVT
simulation for 100ps, and it works well. and did not get any error
until the end.
But as soon as I switch to NPT full production run, I got the
following error. Can any body help me on this issue.
Program mdrun, VERSION 4.0.5
Source code file: constr.c, line: 136
Fatal error:
Too many LINCS warnings (6540)
If you know what you are doing you can adjust the lincs warning
threshold in your mdp file
or set the environment variable GMX_MAXCONSTRWARN to -1,
but normally it is better to fix the problem
my NPT.mdp file is
;
; File 'mdout.mdp' was generated
; By user: teklebrh (182637)
; On host: acs06988
; At date: Fri Feb 19 12:24:32 2010
; LINES STARTING WITH ';' ARE COMMENTS
title = NVT equlibration ; Title of run
cpp = /usr/bin/cpp ; location of cpp on linux
; The following lines tell the program the standard locations where to
find certain files
; VARIOUS PREPROCESSING OPTIONS
; Preprocessor information: use cpp syntax.
; e.g.: -I/home/joe/doe -I/home/mary/hoe
include =
; e.g.: -DI_Want_Cookies -DMe_Too
; RUN CONTROL PARAMETERS
integrator = md
; Start time and timestep in ps
tinit = 0
dt = 0.002
nsteps = 2000000
; For exact run continuation or redoing part of a run
; Part index is updated automatically on checkpointing (keeps files separate)
simulation_part = 1
init_step = 0
; mode for center of mass motion removal
comm-mode = Linear
; number of steps for center of mass motion removal
nstcomm = 1
; group(s) for center of mass motion removal
comm-grps =
; LANGEVIN DYNAMICS OPTIONS
; Friction coefficient (amu/ps) and random seed
bd-fric = 0
ld-seed = 1993
; ENERGY MINIMIZATION OPTIONS
; Force tolerance and initial step-size
emtol = 100
emstep = 0.01
; Max number of iterations in relax_shells
niter = 20
; Step size (ps^2) for minimization of flexible constraints
fcstep = 0
; Frequency of steepest descents steps when doing CG
nstcgsteep = 1000
nbfgscorr = 10
; TEST PARTICLE INSERTION OPTIONS
rtpi = 0.05
; OUTPUT CONTROL OPTIONS
; Output frequency for coords (x), velocities (v) and forces (f)
nstxout = 100
nstvout = 100
nstfout = 100
; Output frequency for energies to log file and energy file
nstlog = 100
nstenergy = 100
; Output frequency and precision for xtc file
nstxtcout = 100
xtc-precision = 1000
; This selects the subset of atoms for the xtc file. You can
; select multiple groups. By default all atoms will be written.
xtc-grps =
; Selection of energy groups
energygrps =
; NEIGHBORSEARCHING PARAMETERS
; nblist update frequency
nstlist = 10
; ns algorithm (simple or grid)
ns-type = Grid
; Periodic boundary conditions: xyz, no, xy
pbc = xyz
periodic_molecules = no
; nblist cut-off
rlist = 0.9
; OPTIONS FOR ELECTROSTATICS AND VDW
; Method for doing electrostatics
coulombtype = PME
rcoulomb-switch = 0
rcoulomb = 0.9
; Relative dielectric constant for the medium and the reaction field
epsilon_r = 1
epsilon_rf = 1
; Method for doing Van der Waals
vdw-type = Cut-off
; cut-off lengths
rvdw-switch = 0
rvdw = 1.4
; Apply long range dispersion corrections for Energy and Pressure
DispCorr = no
; Extension of the potential lookup tables beyond the cut-off
table-extension = 1
; Seperate tables between energy group pairs
energygrp_table =
; Spacing for the PME/PPPM FFT grid
fourierspacing = 0.12
; FFT grid size, when a value is 0 fourierspacing will be used
fourier_nx = 0
fourier_ny = 0
fourier_nz = 0
; EWALD/PME/PPPM parameters
pme_order = 4
ewald_rtol = 1e-05
ewald_geometry = 3d
epsilon_surface = 0
optimize_fft = no
; IMPLICIT SOLVENT ALGORITHM
implicit_solvent = No
; GENERALIZED BORN ELECTROSTATICS
; Algorithm for calculating Born radii
gb_algorithm = Still
; Frequency of calculating the Born radii inside rlist
nstgbradii = 1
; Cutoff for Born radii calculation; the contribution from atoms
; between rlist and rgbradii is updated every nstlist steps
rgbradii = 2
; Dielectric coefficient of the implicit solvent
gb_epsilon_solvent = 2.4
; Salt concentration in M for Generalized Born models
gb_saltconc = 0
; Scaling factors used in the OBC GB model. Default values are OBC(II)
gb_obc_alpha = 1
gb_obc_beta = 0.8
gb_obc_gamma = 4.85
; Surface tension (kJ/mol/nm^2) for the SA (nonpolar surface) part of GBSA
; The default value (2.092) corresponds to 0.005 kcal/mol/Angstrom^2.
sa_surface_tension = 2.092
; OPTIONS FOR WEAK COUPLING ALGORITHMS
; Temperature coupling
tcoupl = v-rescale ; NVT
; Groups to couple separately
tc-grps = PAP TOL
; Time constant (ps) and reference temperature (K)
tau-t = 0.1 0.1
ref-t = 300 300
; Pressure coupling
Pcoupl = berendsen ; no presure coupling in NVT
Pcoupltype = Isotropic
; Time constant (ps), compressibility (1/bar) and reference P (bar)
tau-p = 1
compressibility = 9.2e-5
ref-p = 1
; Scaling of reference coordinates, No, All or COM
refcoord_scaling = No
; Random seed for Andersen thermostat
andersen_seed = 815131
; OPTIONS FOR QMMM calculations
QMMM = no
; Groups treated Quantum Mechanically
QMMM-grps =
; QM method
QMmethod =
; QMMM scheme
QMMMscheme = normal
; QM basisset
QMbasis =
; QM charge
QMcharge =
; QM multiplicity
QMmult =
; Surface Hopping
SH =
; CAS space options
CASorbitals =
CASelectrons =
SAon =
SAoff =
SAsteps =
; Scale factor for MM charges
MMChargeScaleFactor = 1
; Optimization of QM subsystem
bOPT =
bTS =
; SIMULATED ANNEALING
; Type of annealing for each temperature group (no/single/periodic)
annealing =
; Number of time points to use for specifying annealing in each group
annealing_npoints =
; List of times at the annealing points for each group
annealing_time =
; Temp. at each annealing point, for each group.
annealing_temp =
; GENERATE VELOCITIES FOR STARTUP RUN
gen-vel = yes ; assign velocities from Maxwell
distribution (MXD)
gen-temp = 300 ; temperature for MXD
gen-seed = 173529 ; used to initialize random
generator for random velocities
; OPTIONS FOR BONDS
constraints = all-bonds
; Type of constraint algorithm
constraint-algorithm = Lincs
; Do not constrain the start configuration
continuation = no
; Use successive overrelaxation to reduce the number of shake iterations
Shake-SOR = no
; Relative tolerance of shake
shake-tol = 0.0001
; Highest order in the expansion of the constraint coupling matrix
lincs-order = 4
; Number of iterations in the final step of LINCS. 1 is fine for
; normal simulations, but use 2 to conserve energy in NVE runs.
; For energy minimization with constraints it should be 4 to 8.
lincs-iter = 1
; Lincs will write a warning to the stderr if in one step a bond
; rotates over more degrees than
lincs-warnangle = 30
; Convert harmonic bonds to morse potentials
morse = no
; ENERGY GROUP EXCLUSIONS
; Pairs of energy groups for which all non-bonded interactions are excluded
energygrp_excl =
; WALLS
; Number of walls, type, atom types, densities and box-z scale factor
for Ewald
nwall = 0
wall_type = 9-3
wall_r_linpot = -1
wall_atomtype =
wall_density =
wall_ewald_zfac = 3
; COM PULLING
; Pull type: no, umbrella, constraint or constant_force
pull = no
; NMR refinement stuff
; Distance restraints type: No, Simple or Ensemble
disre = No
; Force weighting of pairs in one distance restraint: Conservative or Equal
disre-weighting = Conservative
; Use sqrt of the time averaged times the instantaneous violation
disre-mixed = no
disre-fc = 1000
disre-tau = 0
; Output frequency for pair distances to energy file
nstdisreout = 100
; Orientation restraints: No or Yes
orire = no
; Orientation restraints force constant and tau for time averaging
orire-fc = 0
orire-tau = 0
orire-fitgrp =
; Output frequency for trace(SD) and S to energy file
nstorireout = 100
; Dihedral angle restraints: No or Yes
dihre = no
dihre-fc = 1000
; Free energy control stuff
free-energy = no
init-lambda = 0
delta-lambda = 0
sc-alpha = 0
sc-power = 0
sc-sigma = 0.3
couple-moltype =
couple-lambda0 = vdw-q
couple-lambda1 = vdw-q
couple-intramol = no
; Non-equilibrium MD stuff
acc-grps =
accelerate =
freezegrps =
freezedim =
cos-acceleration = 0
deform =
; Electric fields
; Format is number of terms (int) and for all terms an amplitude (real)
; and a phase angle (real)
E-x =
E-xt =
E-y =
E-yt =
E-z =
E-zt =
; User defined thingies
user1-grps =
user2-grps =
userint1 = 0
userint2 = 0
userint3 = 0
userint4 = 0
userreal1 = 0
userreal2 = 0
userreal3 = 0
userreal4 = 0
Rob
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