[CP2K:7152] MD calculation water on Pt

[Dorothea Golze]

Hi Sergey,

the Siepmann-Sprik potential assumes intact water molecules at the
interface. In your case, some dissociation seems to take place. It is
checked with a simple distance criterion if we have 2 hydrogens per oxygen.
You get the error message:  *Error in Siepmann-Sprik part: too many H
atoms, *i.e. more than 2 hydrogen per oxygen found.
The keyword ALLOW_OH_FORMATION ignores that and doesn't calculate the T3
term of the Siepmann-Sprik potential for this MD step. So the program won't
stop. This keyword was actually intended for cases where water is described
at the QM level, but you can try it as well.
It's  strange that you have this behavior at the SPC level. However, the
temperature development of your MD is very weird and has extreme jumps. So
it's maybe not surprising that your O-H bonds are strangely stretched. So
better control your MD setup and parameters.
btw: examples for the Siepmann-Sprik potential can be found in the
regtests: /cp2k/tests/Fist/regtest-6/

Best regards,
Dorothea


2015-11-12 20:56 GMT+01:00 Sergey Doronin <sedo... at gmail.com>:

> Hi, dear colleagues
>
>
>
> Last weeks I started MD calculation of Pt+H2O system. Water was presented
> by SPC model, Pt-H2O described by Siepmann-Sprik type potential (parameters
> of potential were taken from J.I. Siepmann and M.Sprik // J.Chem.Phys. Vol.
> 102, No. 1, 1995).
>
>
>
> Unfortunately all calculations are terminated as:
>
>
>
> (file *Pt111_1586H2O_Test1*)
>
> *ENERGY| Total FORCE_EVAL ( FIST ) energy (a.u.):
> -31.736442138935644*
>
>
>
>
>
> * Centre of mass motion (COM):                            x =
> -0.0000001751*
>
> *                                                         y =
> 0.0000000386*
>
> *                                                         z =
> -0.0000002641*
>
>
>
>
> * ********************************************************************************
>
> * ENSEMBLE TYPE
> =                                              NVT*
>
> * STEP NUMBER
> =                                             4210*
>
> * TIME [fs]                    =
> 421.000000*
>
> * CONSERVED QUANTITY [hartree] =
> 0.132931078387E+04*
>
>
>
> *                                              INSTANTANEOUS
> AVERAGES*
>
> * CPU TIME [s]                 =
> 0.97                 1.01*
>
> * ENERGY DRIFT PER ATOM [K]    =          0.746520229520E+05
> 0.483172888277E+05*
>
> * POTENTIAL ENERGY[hartree]    =         -0.317364421389E+02
> -0.305625006633E+02*
>
> * KINETIC ENERGY [hartree]     =          0.294647664771E+01
> 0.450202835322E+01*
>
> * TEMPERATURE [K]              =                     195.611
> 298.881*
>
>
> * ********************************************************************************
>
>
>
> * MM DIPOLE [BERRY PHASE](A.U.)|                  -5.474236  -7.277890
> -24.581328*
>
> * MM DIPOLE [BERRY PHASE](Debye)|                -13.914119 -18.498550
> -62.479498*
>
> * MM DIPOLE [BERRY PHASE] DERIVATIVE(A.U.)|       -0.011981  -0.010334
> 0.009710*
>
>
>
> * ENERGY| Total FORCE_EVAL ( FIST ) energy (a.u.):
> 8772.964220420968559*
>
>
>
>
>
> * Centre of mass motion (COM):                            x =
> -0.0000010184*
>
> *                                                         y =
> 0.0000002238*
>
> *                                                         z =
> -0.0000015332*
>
>
>
>
>
>
>
> * ********************************************************
>
> * *** ERROR in siep_Phi_ij (MODULE manybody_siepmann) ****
>
> * ********************************************************
>
>
>
> * *** Error in Siepmann-Sprik part: too many H atoms ****
>
>
>
> * *** Program stopped at line number 338 of MODULE manybody_siepmann ****
>
>
> or sometimes (file *Pt111_1586H2O_Test2*) terminated as
>
>
>
> *Centre of mass motion (COM):                            x =
> -0.0000000528*
>
> *                                                         y =
> -0.0000000109*
>
> *                                                         z =
> -0.0000001862*
>
> * MM DIPOLE [BERRY PHASE](A.U.)|                  -6.717544   2.821496
> -3.847367*
>
> * MM DIPOLE [BERRY PHASE](Debye)|                -17.074293   7.171526
> -9.779030*
>
> * MM DIPOLE [BERRY PHASE] DERIVATIVE(A.U.)|       -0.002798  -0.008723
> 0.005970*
>
>
>
> * ENERGY| Total FORCE_EVAL ( FIST ) energy (a.u.):
> -31.096110069961611*
>
>
>
>
>
> * Centre of mass motion (COM):                            x =
> -0.0000000505*
>
> *                                                         y =
> -0.0000000105*
>
> *                                                         z =
> -0.0000001776*
>
> * MM DIPOLE [BERRY PHASE](A.U.)|                  -6.729504   2.834566
> -3.852281*
>
> * MM DIPOLE [BERRY PHASE](Debye)|                -17.104691   7.204748
> -9.791520*
>
> * MM DIPOLE [BERRY PHASE] DERIVATIVE(A.U.)|       -0.002638  -0.008331
> 0.005670*
>
>
>
> * ENERGY| Total FORCE_EVAL ( FIST ) energy (a.u.):
> 96420902.412601232528687*
>
>
>
>
>
> * ***********************************************************************
>
> * ***********************************************************************
>
> * *** 22:43:43 ERRORL3 in thermostat_utils:communication_thermo_low1 ****
>
> * *** processor 0  :: err=-300 condition FAILED at line 1877         ****
>
> * ***********************************************************************
>
> * ***********************************************************************
>
>
>
>
>
> I’ve varied the basic parameters to solve the problem: time steps,
> temperature, type and parameters of thermostat, Pt-O potential in &genpot
> section and etc. But all manipulation doesn’t give anything. Anyway, each
> task has a jump of energy at last iteration. A network also doesn’t have
> any information.
>
>
>
> Can anyone please help me to solve this problem? Maybe someone work with
> Siepmann potential?
>
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