SG-15 Norm Conserving PP

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Kayahan
Posts: 22
Joined: Fri Jun 07, 2013 5:56 pm

SG-15 Norm Conserving PP

Post by Kayahan »

Dear CASINO Users,

I wanted to test some of the SG-15 PP, found in the PWSCF library (http://materialscloud.org). Converting the UPF format into CASINO works fine, and results the attached cl_pp.data file for Cl atom. However, SG-15 PP are designed in a way that local potential does not have to be the maximum angular momentum, they are usually any value larger than the max angular momentum. For Cl, maximum angular momentum is 1 and local channel is 4. The conversion script, therefore, outputs exactly the same columns for l=2, l=3 and l=4, which equals to the local potential. would this be OK to use? I erased the l=2 and l=3 parts, but then I get the error saying that
Error reading cl_pp.data: angular momentum components not in order of increasing l.
. Thanks a lot for your help in advance and please let me know if you need any more information. I also included the output of PWSCF and CASINO vmc output for your reference.

Best,
Kayahan
Attachments
results.zip
(203.21 KiB) Downloaded 678 times
17Cl.oncvpsp.upf.zip
(42.54 KiB) Downloaded 696 times
cl_pp.data.zip
(16.5 KiB) Downloaded 706 times
Katharina Doblhoff
Posts: 84
Joined: Tue Jun 17, 2014 6:50 am

Re: SG-15 Norm Conserving PP

Post by Katharina Doblhoff »

Am I mistaken, or are the SG-15 Optimized Norm Conserving PPs?! They have several projection channels for one angular momentum. This is not compatible with the current way of using PPs in Casino (and other QMC codes). The way how PPs are evaluated comparatively efficiently in QMC is by using a Lebedev quadrature for the angular integration to project out one L channel. If the projectors are L and r dependent (such as the ONCPs by Hamann), one would need an additional r-Integration which would be too costly when using a correlated Slater-Jastrow function for the PP evaluation.
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