[gpaw-users] Generating a core-hole setup with generator2

[Eric Hermes]

Marcin,

Is there an optimized dataset for ruthenium? I wish to benchmark my 
methodology against a literature result, and the paper to which I am 
comparing is studying oxygen-covered ruthenium. If there isn't an 
optimized dataset, do you believe it is safe to use the old generator 
for the time being?

Thanks,
Eric Hermes

On 3/20/2015 1:23 PM, Marcin Dulak wrote:
> Hi,
>
> On 03/20/2015 04:50 PM, Eric Hermes wrote:
>> Marcin,
>>
>> On 3/20/2015 6:56 AM, Marcin Dulak wrote:
>>> Hi,
>>>
>>> On 03/19/2015 07:16 PM, Eric Hermes wrote:
>>>> Hello,
>>>>
>>>> I am attempting to generate a setup for Pd with a core hole in the 
>>>> 3d state using generator2. If I generate the setup with '-f PBE -w 
>>>> -s Pd --core-hole 3d,1.0', several new additional bound states 
>>>> appear that did not exist in the ground-state calculation (2 
>>>> s-states, 2 p-states, and 3 d-states). Here is an example output 
>>>> from this calculation:
>>>> https://gist.github.com/ehermes/6c85184e16d43acb6992
>>>>
>>>> If I instead generate the setup by specifying the electron 
>>>> configuration with '-C' (as [Ar] 3s2 3p6 3d9 4s2 4p6 4d10 5s1), I 
>>>> receive no error and get what appears to be a working core-hole 
>>>> setup for Pd. In addition, the total all-electron 
>>>> scalar-relativistic energy difference between the ground state and 
>>>> core-hole Pd atom is quite close to the experimental metallic Pd 3d 
>>>> binding energy (334.2 eV vs ~335.2 eV). This indicates to me that 
>>>> this procedure works. However, I am not using the "--core-hole" 
>>>> argument to do this. Is what I am doing valid? Here's the output 
>>>> file from the calculation I have described:
>>>> https://gist.github.com/ehermes/3aec73bb427bbc6efe7c
>>>>
>>>> Also, I understand that the setups used for the ground state Pd and 
>>>> core-excited Pd should be of comparable quality, and that the best 
>>>> way to ensure this is to generate both setups as similarly as 
>>>> possible. However, the default setup parameters for Pd in 
>>>> generator2 do not seem to produce a good quality setup. While the 
>>>> official setups produce lattice constants (3.946 for 10-electron 
>>>> and 3.937 for 18-electron) that are in fairly good agreement with 
>>>> an all-electron FP-LAPW calculation (3.948 angstrom), the default 
>>>> Pd setup generated by generator2 predicts a lattice constant that 
>>>> is more than 0.02 angstrom too large (3.972). If I use the cutoffs 
>>>> from the official 10-electron setup ([2.3, 2.5, 2.2]) instead of 
>>>> generator2's default cutoff (2.4), the lattice constant is in much 
>>>> better agreement (3.958). As I am not an expert in generating 
>>>> pseudopotentials, I wonder what the best procedure here is, and how 
>>>> to best measure the quality of a setup. Any advice would be 
>>>> appreciated.
>>> i would not use the non-semicore datasets (that's how we call setups 
>>> now) like Pd 10-electron anymore.
>>> Most modern pseudopotentials (http://www.physics.rutgers.edu/gbrv/ 
>>> http://fpmd.ucdavis.edu/qso/potentials/index.htm 
>>> http://www.abinit.org/downloads/PAW2/OLD-VERSIONS/JTH-TABLE-0.1/index.html)
>>> dropped the idea of non-semicore ones because they are more 
>>> difficult to create.
>>> We don't have a working 10-electron Pd in generator2 (yet?). The 
>>> parameters for non-semicore datasets in generator2.py are just so 
>>> there is something there - they are not meant to be used.
>>> On the other hand we have an "optimized" version of 18-electron Pd:
>>> python -c "from gpaw.atom.generator2 import main as g; g(['Pd', 
>>> '-f', 'PBE', '-sw', '-P', '4s,5s,4p,5p,4d,0.5d,F', '-r', 
>>> '1.98,2.5,2.05', '-0', '5,1.69', '-pl', 'spdfg,-1.5:1.5:0.01'])"
>>> Try starting from the above.
>>
>> Where do those parameters come from? I do not see them in 
>> generator2.py. How trustworthy are the default parameters in 
>> generator2.py? Where can I find the dataset parameters for the 
>> elements that have been "optimized"?
> this is still work in progress, but we are "optimizing" all elements.
>
> Best regards,
>
> Marcin
>>
>>> Best regards,
>>>
>>> Marcin
>>>>
>>>> Thank you,
>>>> Eric Hermes
>>>>
>>>
>>>
>>
>

-- 
Eric Hermes
J.R. Schmidt Group
Chemistry Department
University of Wisconsin - Madison