[CPMD-list] position restraints not working

Ari P Seitsonen ari.p.seitsonen at iki.fi
Sat May 20 00:34:46 CEST 2006


Dear Martin,

   I don't know for 100 % sure, but at least earlier many of the 
restraints and constraints did not work with geometry optimisation, only 
with MD. Of course in small molecules the former would be more efficient, 
however the larger the molecule, the more efficient is simulated 
annealing, and that of course include the MD.

   Sorry for that; or maybe some one else knows better?

     Greetings from Paris,

        apsi

-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-
   Ari P Seitsonen / Ari.P.Seitsonen at iki.fi / http://www.iki.fi/~apsi/
   GSM: +33-6-6736 3820

On Fri, 19 May 2006, Martin Konopka wrote:

> Dear Ari,
>
> Thank you. I looked into setsys.F and really, the conversion of the units 
> looks to be missing there for position restraints. (For some other kinds of 
> restraints the conversion is implemented.) MD in my test worked correctly 
> when supplying the input in A.U.; also the frequency of the osillations was 
> as it should be.
>
> I am not so sure about the geometry optimization - even setting kval to 100 
> A.U.
> (and setting a tough convergence criteria) does not attract the atoms into 
> the restraint centers and the optimization stops somehow early. You can see 
> my input file below and also a piece of the output.
>
> I put the TESR 2 into my previous input file just by a mistake.
>
> &CPMD
>  OPTIMIZE GEOMETRY
>  CONVERGENCE
>    1.0D-7  1.0D-5
>  CONVERGENCE CALFOR
>    1.01D0
>  CONVERGENCE RELAX
>    20
>  SPLINE POINTS QFUNCTION
>    2001
> &END
>
> &DFT
>  FUNCTIONAL PBE
>  GC-CUTOFF
>    1.0D-7
> &END
>
> &SYSTEM
>  SYMMETRY
>    0
>  POISSON SOLVER TUCKERMAN
>  CELL ABSOLUTE
>    11.3383568035275  11.3383568035275  18.8972613392125    0.0  0.0  0.0
>  CUTOFF
>    70.0D0
> &END
>
> &ATOMS
> *H-q1
>  LMAX=S
>   2
>     5.68807566310297  5.70697292444218  14.1540487430702
>     5.63138387908533  5.68807566310297   4.6865208121247
> CONSTRAINTS
>  RESTRAINTS
>    2
>    RESPOS  1   5.66917840176376  5.66917840176376  14.1729460044094    0.0 
> 100.0
>    RESPOS  2   5.66917840176376  5.66917840176376  4.72431533480313    0.0 
> 100.0
> END CONSTRAINTS
> &END
>
> ****************************************************************
> *** TOTAL STEP NR.    94           GEOMETRY STEP NR.      9  ***
> *** GNMAX=  2.980845E+00 [5.86E-08]     ETOT=     -0.920301  ***
> *** GNORM=  1.798356E+00               DETOT=     7.356E-13  ***
> *** CNSTR=  0.000000E+00                TCPU=          1.88  ***
> ****************************************************************
> ================================================================
> =              END OF GEOMETRY OPTIMIZATION                    =
> ================================================================
>
>
>
> RESTART INFORMATION WRITTEN ON FILE                  ./RESTART.1
>
>
>                     <<<<< RESTRAINTS >>>>>
> RESTRAINED STRUCTURE ELEMENTS
>      TYPE     ATOM ATOM ATOM ATOM       VALUE     FORCE CONSTANT
>    RESPOS        1 5.67 5.6714.17     0.00000          100.0
>    RESPOS        2 5.67 5.67 4.72     0.00000          100.0
>
>
> ****************************************************************
> *                                                              *
> *                        FINAL RESULTS                         *
> *                                                              *
> ****************************************************************
>
>   ATOM          COORDINATES            GRADIENTS (-FORCES)
>   1  H  5.6960  5.6772 14.1787   2.687E+00  7.977E-01  5.772E-01
>   2  H  5.6394  5.6583  4.7136  -2.981E+00 -1.092E+00 -1.067E+00
>
>
>                     <<<<< RESTRAINTS >>>>>
> RESTRAINED STRUCTURE ELEMENTS
>      TYPE     ATOM ATOM ATOM ATOM       VALUE     FORCE CONSTANT
>    RESPOS        1 5.67 5.6714.17     0.00000          100.0
>    RESPOS        2 5.67 5.67 4.72     0.00000          100.0
>
>
> Greetings,
> Martin.
>
>
>
> On Fri, 19 May 2006 11:55:36 +0200 (CEST)
> Ari P Seitsonen <ari.p.seitsonen at iki.fi> wrote:
>> 
>> Dear Martin,
>>
>>   Did you try giving the constrained position in Bohr instead of Angstrom? 
>> With this change your input seemed to work... No guarantee though. ;)
>>
>>     Greetings from Paris,
>>
>>        apsi
>> 
>> PS The combination SYMMETRY 0 / TESR 2 sound a bit contradictory to me,
>>   maybe it's just because this is a "toy" system?
>>
>> 
>> -=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-
>>   Ari P Seitsonen / Ari.P.Seitsonen at iki.fi / http://www.iki.fi/~apsi/
>>   GSM: +33-6-6736 3820
>> 
>> On Thu, 18 May 2006, Martin Konopka wrote:
>> 
>>> Dear CPMD developers,
>>> 
>>> I am trying to use the position restraints implemented in CPMD 3.11.1.
>>> It seems failing to work. Restraints are not kept. You can see my test
>>> example in test_respos_H2.tar.bz2 . (It is rather artificial system
>>> - just for the test purpose.)
>>> 
>>> I have also my own implementation of position restraints (which I
>>> programmed very recently not knowing that position restraints are
>>> to become available in CPMD 3.11.1). My implementation works (but not
>>> with geometry optimization). It is only slighly less general in the
>>> sense that it uses d0 = 0. If there is an interest I can send patch
>>> files for my implementation or even try to correct the existing
>>> official implementation in 3.11.1 - please let me know what do you think
>>> about it.
>>> 
>>> Greetings,
>>> Martin Konopka.
>>> 
>>> ------------------------------------------------------------
>>> Dr. Martin Konopka                   tel: +421-(0)2-60291714
>>> Dept. of Physics, CCMS               fax: +421-(0)2-65411483
>>> Slovak University of Technology
>>> Ilkovicova 3, 812 19 Bratislava, Slovakia
>>> 
>>> http://www.ccms.elf.stuba.sk/konopka.html
>>> ------------------------------------------------------------
>>> 
>
> ------------------------------------------------------------
> Dr. Martin Konopka                   tel: +421-(0)2-60291714
> Dept. of Physics, CCMS               fax: +421-(0)2-65411483
> Slovak University of Technology
> Ilkovicova 3, 812 19 Bratislava, Slovakia
>
> http://www.ccms.elf.stuba.sk/konopka.html
> ------------------------------------------------------------
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