[CP2K:1801] Re: non-orthorhomic variable cell optimization

Teodoro Laino teodor... at gmail.com
Wed Feb 25 18:21:22 UTC 2009


Dear Rad,
There is no bug coming from my previous patch. The CELL_OPT is working 
properly and what you see is
something system dependent.

Teo

Rad wrote:
> Dear Teo,
>
> Thank you for your response and the fix has partially worked in the
> sense
> that it prints the correct lattice parameters in the 0th step as the
> input.
> However, it looks like the fix has broken other parts of the code. One
> of
> the systems I tried had volume going from 400 A3 to 1000 A3 during the
> second step
> Of the optimization and then the calculation stalled. The same
> calculation
> used to run smoothly before the fix except for the problem I reported
> earlier. I am attaching here with the input I tested along with the
> associated POTENTIAL and BASIS_SET files. You can run the input using
> an
> executable before the fix as well as after the fix and compare the
> behavior.
> Please take a look at this issue or someone from the team to resolve
> this at
> your convenience. I really appreciate the prompt response we get from
> the
> cp2k team and please feel free to ask if you need more information
> about the
> input.
>
> I have uploaded three files with the prefix "RAD_TEST" and please let
> me know if you trouble accessing them.
>
> Thanks
> Rad
>
>
> On Feb 17, 3:07 pm, Teodoro Laino <teodor... at gmail.com> wrote:
>   
>> Hi Rad,
>> actually, there was a bug when handling triclinic cells (in the
>> optimization module).
>> The bug fix is in the CVS.
>> Thanks,
>> Teo
>>
>>
>>
>> Rad wrote:
>>     
>>> Dear Monica,
>>>       
>>> Thank you for your response and I really appreciate it. I would like
>>> to clarify further about my earlier posting as it relates to the
>>> behavior of the variable cell optimization module.
>>>       
>>> We are getting reasonable results using the variable cell optimization
>>> module when it comes to non-monoclinic cells. But We have observed
>>> consistently in the case of triclinic cells is a change in the lattice
>>> vectors from the given input even before taking an optimization step.
>>>  It is as if the module is starting with a different initial
>>> configuration.
>>>       
>>> Our intention is to understand the process the module follows so that
>>> we can be comfortable with the final output it produces. For example,
>>> in one of our studies we gave the following input:
>>>       
>>> In this case we are providing the experimental lattice configuration
>>> as the input.
>>>       
>>>  CELL| Vector a [ANGSTROM]:       9.814     0.000     0.000    |
>>> a|      =       9.814
>>>  CELL| Vector b [ANGSTROM]:       0.424     9.038     0.000    |b|
>>> =       9.048
>>>  CELL| Vector c [ANGSTROM]:       1.575     0.001    20.279    |c|
>>> =      20.340
>>>  CELL| Angle (b,c)
>>> [degree]:                                              89.790
>>>  CELL| Angle (a,c)
>>> [degree]:                                              85.559
>>>  CELL| Angle (a,b)
>>> [degree]:                                              87.314
>>>       
>>> Then after the initial set up the module prints the following
>>> configuration at the 0th step: (This 0th step is before any prior
>>> calculation has happened)
>>> ANGSTROM**3]:                                            1795.645
>>>  CELL| Vector a [ANGSTROM]:       9.807     0.000     0.000    |a|
>>> =       9.807
>>>  CELL| Vector b [ANGSTROM]:       0.424     9.031     0.000    |b|
>>> =       9.041
>>>  CELL| Vector c [ANGSTROM]:       1.575    -0.001    20.276    |c|
>>> =      20.337
>>>  CELL| Angle (b,c)
>>> [degree]:                                              89.795
>>>  CELL| Angle (a,c)
>>> [degree]:                                              85.559
>>>  CELL| Angle (a,b)
>>> [degree]:                                              87.312
>>>       
>>> This strange switch in the initial geometry is happening only in the
>>> case of triclinic cells. In addition, the final output volume is off
>>> by more than 10% in some cases. This is what prompted us to go over
>>> the output in detail and come up with a pattern.
>>> It would help us understand and be comfortable with the results if we
>>> know what is happening at the 0th step and what prompts the change in
>>> the configuration only for monoclinic cells.
>>>       
>>> If the developers can take a look at the pattern and provide us with
>>> any suggestions we would appreciate it.
>>>       
>>> Thanks
>>> Rad
>>>       
>>> On Feb 13, 9:33 am, monica <monic... at phys.chem.ethz.ch> wrote:
>>>       
>>>> Dear Rad,
>>>>         
>>>> I was running recently several triclinic cell optimization jobs
>>>> (although the angles are very close to 90), with variable hydrostatic
>>>> pressure (0-20 GPa), and it seemed to work: when comparing the volume
>>>> with similar orthorhombic cell, optimized manually (energy volume
>>>> curve). See output below for example. In my case, when the cell was
>>>> already close to the minimum, only minor changes occurred.
>>>>         
>>>> Monica
>>>>         
>>>> output for example
>>>>  CELL| Volume
>>>> [ANGSTROM**3]:                                            1798.737
>>>>  CELL| Vector a [ANGSTROM]:       9.814     0.000     0.000    |a|
>>>> =       9.814
>>>>  CELL| Vector b [ANGSTROM]:       0.424     9.038     0.000    |b|
>>>> =       9.048
>>>>  CELL| Vector c [ANGSTROM]:       1.575     0.001    20.279    |c|
>>>> =      20.340
>>>>  CELL| Angle (b,c)
>>>> [degree]:                                              89.790
>>>>  CELL| Angle (a,c)
>>>> [degree]:                                              85.559
>>>>  CELL| Angle (a,b)
>>>> [degree]:                                              87.314
>>>>  CELL| Grid size for subcell
>>>> generation                                    2.000
>>>>  CELL| Volume
>>>> [ANGSTROM**3]:                                            1795.645
>>>>  CELL| Vector a [ANGSTROM]:       9.807     0.000     0.000    |a|
>>>> =       9.807
>>>>  CELL| Vector b [ANGSTROM]:       0.424     9.031     0.000    |b|
>>>> =       9.041
>>>>  CELL| Vector c [ANGSTROM]:       1.575    -0.001    20.276    |c|
>>>> =      20.337
>>>>  CELL| Angle (b,c)
>>>> [degree]:                                              89.795
>>>>  CELL| Angle (a,c)
>>>> [degree]:                                              85.559
>>>>  CELL| Angle (a,b)
>>>> [degree]:                                              87.312
>>>>  CELL| Grid size for subcell
>>>> generation                                    2.000
>>>>  CELL| Volume
>>>> [ANGSTROM**3]:                                            1785.878
>>>>  CELL| Vector a [ANGSTROM]:       9.783     0.000     0.000    |a|
>>>> =       9.783
>>>>  CELL| Vector b [ANGSTROM]:       0.424     9.008     0.000    |b|
>>>> =       9.018
>>>>  CELL| Vector c [ANGSTROM]:       1.574    -0.006    20.266    |c|
>>>> =      20.327
>>>>  CELL| Angle (b,c)
>>>> [degree]:                                              89.810
>>>>  CELL| Angle (a,c)
>>>> [degree]:                                              85.560
>>>>  CELL| Angle (a,b)
>>>> [degree]:                                              87.307
>>>>         
>>>> On Feb 11, 10:47 pm, Rad <rad.... at arl.army.mil> wrote:
>>>>         
>>>>> Hello everybody,
>>>>>           
>>>>> We seem to be having an issue with non-orthorhombic cell optimization
>>>>> when the lattice has all the three angles other than 90 degrees. Here
>>>>> is what appears to be happening: After the initial set up, the module
>>>>> Changes the lattice vectors by keeping the lengths the same but the
>>>>> angles are slightly different. This happens only when all the angles
>>>>> are not 90-degrees. The regtest for non-orthorhombic includes only one
>>>>> angle 120 and the rest are 90s. So the scenario I described might be
>>>>> missed out. This issue we have observed in several executables we have
>>>>> built over the last several months and on multiple architectures.
>>>>>           
>>>>> ===========================================================================­­=======
>>>>> Here is the output just after the set up which is the same as the
>>>>> input:
>>>>> CELL| Volume
>>>>> [ANGSTROM**3]:                                             442.524
>>>>>  CELL| Vector a [ANGSTROM]:       9.010     0.000     0.000    |a|
>>>>> =       9.010
>>>>>  CELL| Vector b [ANGSTROM]:      -4.510     7.821     0.000    |b|
>>>>> =       9.028
>>>>>  CELL| Vector c [ANGSTROM]:      -0.216    -2.630     6.280    |c|
>>>>> =       6.812
>>>>>  CELL| Angle (b,c)
>>>>> [degree]:                                             108.580
>>>>>  CELL| Angle (a,c)
>>>>> [degree]:                                              91.820
>>>>>  CELL| Angle (a,b)
>>>>> [degree]:                                             119.970
>>>>>           
>>>>> Here is when it got changed just before the first step of the
>>>>> optimization:
>>>>>           
>>>>>  CELL| Volume
>>>>> [ANGSTROM**3]:                                             449.960
>>>>>  CELL| Vector a [ANGSTROM]:       9.010     0.000     0.000    |a|
>>>>> =       9.010
>>>>>  CELL| Vector b [ANGSTROM]:      -4.510     7.821     0.000    |b|
>>>>> =       9.028
>>>>>  CELL| Vector c [ANGSTROM]:      -0.216    -2.363     6.386    |c|
>>>>> =       6.812
>>>>>  CELL| Angle (b,c)
>>>>> [degree]:                                             106.534
>>>>>  CELL| Angle (a,c)
>>>>> [degree]:                                              91.820
>>>>>  CELL| Angle (a,b)
>>>>> [degree]:                                             119.970
>>>>>  CELL| Grid size for subcell
>>>>> generation                                    2.000
>>>>>           
>>>>>  --------  Informations at step =     0 ------------
>>>>>   Optimization Method        =                   SD
>>>>>   Total Energy               =      -386.4717739715
>>>>>   Internal Pressure [bar]    =     18296.7247113471
>>>>>  ---------------------------------------------------
>>>>>           
>>>>>  --------------------------
>>>>>  OPTIMIZATION STEP:      1
>>>>> ===========================================================================­­======
>>>>> Could someone please take a look at this issue and let me know what
>>>>> might be the issue.
>>>>>           
>>>>> Thanks
>>>>> Rad- Hide quoted text -
>>>>>           
>>>> - Show quoted text -- Hide quoted text -
>>>>         
>> - Show quoted text -
>>     
> >
>   




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