%METAVAR%TEMP_TOL Vs. %METAVAR%WALL

[Francesco]

Hi Teo, thanks for the reply.

Just a question: In the output doesn't appear the temperature of the
fictious particle I set with the keyword %ROOT%MOTION%FREE_ENERGY
%METADYN%TEMPERATURE and with every value that I put as %ROOT%MOTION
%FREE_ENERGY%METADYN%TEMP_TOL in the log file appears

 METADYN| Collective Variables Temperature
control                          0.00

Why?

Thanks AGAIN
Francesco




On Jun 20, 6:58 pm, Teodoro Laino <teodor... at gmail.com> wrote:
> Francesco,
>
> if you don't put TEMP_TOL no temperature rescaling is performed over
> the collective variables.
> If you put TEMP_TOL the temperature of the COLVAR is rescaled
> according the tolerance.
> Now let me comment your message:
>
> >> I've had some problems to
> >> add the walls on the colvar, since I found difficult to turn them on.
>
> walls are automatically turned on if you ask for them in the input
> file (if not provide an
> input, fast enough to be run (this usually means not more than few
> SECONDS) for
> debugging. The input file you provided merged in your message does
> not show any
> problem to me (as long as I was patience enough to run it)).
>
>
>
> >> In principle, there is a wall_minus at -4 and a wall_plus at +4,
> >> colvar is around -2 at
> >> the beginning of the simulation. To test that the walls were
> >> active, I
> >> did a very simple
> >> test.  I put wall_minus at +4 and wall_plus at -4.
> >> This way, at the first MD step I should find crazy potential energy.
>
> Very laudable effort.. BUT this is not the case since velocities are
> rescaled in between
> the velocity verlet.. so if you have temp_tol on you will never see
> the potential going crazy
> because velocities of the particles are rescaled to the value you
> requested.
>
> >> However, if I set any TEMP_TOL (from 0.0 to 1.E10) for the METAVAR
> >> %ROOT%MOTION%FREE_ENERGY%METADYN%TEMP_TOL
> >> nothing happens, the potential energy at the first MD step is the
> >> total scf energy.
>
> See above.
>
>
>
> >> As I simply remove the TEMP_TOL for the METAVAR from the input, the
> >> potential energy at
> >> the first MD step, as expected, goes crazy because of the walls.
>
> See above.
>
> >> In short, it seems to me that the walls are active if TEMP_TOL on the
> >> METAVAR is not
> >> included in the input.
>
> wrong conclusion. WALLS and TEMP_TOL have two independent setup.
>
> >> Is it that normal ? Am I missing something of
> >> the story ?
>
> If you think how MD works it will be everything clear to you
> (consider that velocities are
> rescaled immediately after the integration).
>
> cheers,
> Teo
>
>
>
> >> Here is the input for a fast (less then 5 mins on a Xeon quadcore)
> >> test.
> >> Thanks,
> >> francesco
>
> >> &MOTION
> >>    &MD
> >>      COMVEL_TOL 1.0E-08
> >>      ANGVEL_ZERO T
> >>      ENSEMBLE NVT
> >>      TEMPERATURE 300.0
> >>      STEPS 10
> >>      TIMESTEP 0.5
> >>      &THERMOSTAT
> >>         TYPE NOSE
> >>         REGION GLOBAL
> >>         &NOSE
> >>         &END NOSE
> >>      &END THERMOSTAT
> >>    &END MD
> >>    &FREE_ENERGY
> >>      METHOD METADYN
> >>      &METADYN
> >>        DO_HILLS F
> >>        LAGRANGE T
> >>        TEMPERATURE 300.0
> >>        TEMP_TOL 80.0
> >>        WW 0.0005
> >>        &METAVAR
> >>          MASS 10.0
> >>          SCALE 0.15
> >>          LAMBDA 0.5
> >>          COLVAR 1
> >>          &WALL
> >>            TYPE QUADRATIC
> >>            POSITION 4.0
> >>            &QUADRATIC
> >>              K 100.0
> >>              DIRECTION WALL_MINUS
> >>            &END QUADRATIC
> >>          &END WALL
> >>          &WALL
> >>            TYPE QUADRATIC
> >>            POSITION -4.0
> >>            &QUADRATIC
> >>              K 100.0
> >>              DIRECTION WALL_PLUS
> >>            &END QUADRATIC
> >>          &END WALL
> >>        &END METAVAR
> >>        &PRINT
> >>          &COLVAR
> >>            FILENAME =colvar
> >>          &END COLVAR
> >>        &END PRINT
> >>      &END METADYN
> >>    &END FREE_ENERGY
> >>    &PRINT
> >>      &TRAJECTORY
> >>        &EACH
> >>          MD 2
> >>        &END EACH
> >>      &END TRAJECTORY
> >>      &VELOCITIES
> >>        &EACH
> >>          MD 2
> >>        &END EACH
> >>      &END VELOCITIES
> >>      &RESTART
> >>        &EACH
> >>          MD 10
> >>        &END EACH
> >>      &END RESTART
> >>    &END PRINT
> >>    &GEO_OPT
> >>    &END GEO_OPT
> >> &END MOTION
> >> &FORCE_EVAL
> >>    METHOD Quickstep
> >>    &DFT
> >>       &POISSON
> >>           POISSON_SOLVER WAVELET
> >>           PERIODIC NONE
> >>       &END POISSON
> >>       BASIS_SET_FILE_NAME BASIS_AU
> >>       POTENTIAL_FILE_NAME POT_AU
> >>       CHARGE -1
> >>      &MGRID
> >>        CUTOFF 280
> >>      &END MGRID
> >>      &QS
> >>        EXTRAPOLATION ASPC
> >>        EXTRAPOLATION_ORDER 3
> >>      &END QS
> >>      &SCF
> >>        EPS_SCF 1.0E-6
> >>        SCF_GUESS ATOMIC
> >>        &PRINT
> >>          &RESTART OFF
> >>          &END
> >>        &END PRINT
> >>        &OT
> >>          MINIMIZER DIIS
> >>          N_DIIS 7
> >>          PRECONDITIONER FULL_SINGLE_INVERSE
> >>        &END OT
> >>        &OUTER_SCF
> >>          EPS_SCF 1.0E-4
> >>          MAX_SCF 4
> >>        &END OUTER_SCF
> >>      &END SCF
> >>      &XC
> >>        &XC_FUNCTIONAL BLYP
> >>        &END XC_FUNCTIONAL
> >>      &END XC
> >>    &END DFT
> >>    &SUBSYS
> >>      &CELL
> >>        ABC 12.0 12.0 12.0
> >>        UNIT ANGSTROM
> >>        PERIODIC NONE
> >>      &END CELL
> >>      &COORD
> >>   C      6.21755040790000        6.27945039380000
> >> 5.87094203540000
> >>   Cl     8.06896049700000        6.19655506190000
> >> 6.18039982360000
> >>   Cl     3.14468329460000        5.68026996200000
> >> 5.90402508870000
> >>   H      5.81537329980000        6.79388677010000
> >> 6.75597666210000
> >>   H      5.90571792570000        5.23287421340000
> >> 5.79791183930000
> >>   H      6.05556449220000        6.86392371860000
> >> 4.95315969410000
> >>      &END COORD
> >>      &VELOCITY
> >>   -2.214634000000000E-004 -2.388178000000000E-004
> >> -4.611093000000000E-004
> >>   -3.043920000000000E-005  6.815900000000000E-005
> >> 1.200276000000000E-004
> >>    1.033677000000000E-004  4.250750000000000E-005
> >> 6.534730000000000E-005
> >>   -3.199348000000000E-004 -1.111403800000000E-003
> >> -3.637730000000000E-005
> >>    3.678017000000000E-004  2.676782000000000E-004
> >> -7.108579000000001E-004
> >>    2.604120000000000E-005 -2.029183000000000E-004
> >> -2.782362000000000E-004
> >>      &END VELOCITY
> >>      &KIND H
> >>        BASIS_SET DZVP-GTH-BLYP
> >>        POTENTIAL GTH-BLYP-q1
> >>      &END KIND
> >>      &KIND C
> >>        BASIS_SET DZVP-GTH-BLYP
> >>        POTENTIAL GTH-BLYP-q4
> >>      &END KIND
> >>      &KIND Cl
> >>        BASIS_SET DZVP-GTH-BLYP
> >>        POTENTIAL GTH-BLYP-q7
> >>      &END KIND
> >>      &COLVAR
> >>        &DISTANCE_DIFFERENCE
> >>           ATOMS 1 2 1 3
> >>        &END DISTANCE_DIFFERENCE
> >>      &END COLVAR
> >>    &END SUBSYS
> >> &END FORCE_EVAL
> >> &GLOBAL
> >>    RUN_TYPE MD
> >>    PROJECT cp2k
> >>    PRINT_LEVEL LOW
> >> &END GLOBAL