Search found 165 matches

by Vladimir_Konjkov
Sat Mar 16, 2024 3:45 pm
Forum: The CASINO program
Topic: molden2qmc
Replies: 45
Views: 343271

Re: molden2qmc

A good way to check if the orbitals have been parsed correctly is to compute the molecular orbital overlap matrix, which should give you the identity matrix. The overlap matrix is also very cheap to compute, even for large systems. I think it's worth doing this check.
by Vladimir_Konjkov
Fri Jan 19, 2024 12:42 pm
Forum: The CASINO program
Topic: Nitrogen molecule with PP and AE atoms.
Replies: 8
Views: 2353

Re: Nitrogen molecule with PP and AE atoms.

Great to read you, Mike. The manual says 6.1.2 Pseudopotentials: On the rare occasions when you might want to use two or more different pseudopotentials for atoms with the same atomic number (say in a surface, and in an atom or molecule absorbed on that surface), then you may use additional pseudopo...
by Vladimir_Konjkov
Mon Jan 15, 2024 3:42 pm
Forum: The CASINO program
Topic: Nitrogen molecule with PP and AE atoms.
Replies: 8
Views: 2353

Re: Nitrogen molecule with PP and AE atoms.

Does the trick of looking at a N"P" (nitrogen "phosphide") molecule, where the nitrogen is all-electron and the phosphorus is actually a pseudonitrogen atom not work? Best wishes, Neil. It seemed to me that this was some kind of puzzle, I need time to think about it. :lol: :lol:...
by Vladimir_Konjkov
Mon Jan 15, 2024 12:16 pm
Forum: The CASINO program
Topic: Nitrogen molecule with PP and AE atoms.
Replies: 8
Views: 2353

Re: Nitrogen molecule with PP and AE atoms.

CASINO allows you to have both all-electron and pseudopotential ions present. For an example, see CASINO/examples/molecule/silane/ground_state which has a silicon pseudopotential, while the hydrogen atoms are all-electron. I can do that! I cannot make it so that in a nitrogen molecule one atom has ...
by Vladimir_Konjkov
Mon Jan 15, 2024 3:59 am
Forum: The CASINO program
Topic: Nitrogen molecule with PP and AE atoms.
Replies: 8
Views: 2353

Re: Nitrogen molecule with PP and AE atoms.

Hello Neil I write tests for my program, and since the input is the same as yours, so for yours. I need such a test so that there are atoms with and without pseudopotential. I can take B2H6 and set the pseudopotential only for hydrogen, the energy should be the same as for B2H6 without the pseudopot...
by Vladimir_Konjkov
Sat Jan 13, 2024 2:09 pm
Forum: The CASINO program
Topic: Nitrogen molecule with PP and AE atoms.
Replies: 8
Views: 2353

Nitrogen molecule with PP and AE atoms.

Dear Casino developers. I want to perform a test calculation of a nitrogen molecule in which one atom has a pseudopotential and the other does not. I attach the input and output files for ORCA that were used for the calculation of gwfn.data. In ORCA calculation dipole moment differs slightly from ze...
by Vladimir_Konjkov
Tue Dec 19, 2023 1:36 am
Forum: Quantum Monte Carlo
Topic: Goodhart's law and VMC optimization.
Replies: 2
Views: 13521

Re: Goodhart's law and VMC optimization.

Hello Neil. I meant that it is very difficult to optimize DMC energy for single determinant Slater-Jastrow-Backflow (SD-SJB) WFN, however it is easy to optimize VMC energy instead. I'll plan to look at correlation of VMC energy and DMC energy for next year, but for now I'm just thinking about it, be...
by Vladimir_Konjkov
Mon Dec 18, 2023 6:11 am
Forum: Quantum Monte Carlo
Topic: Goodhart's law and VMC optimization.
Replies: 2
Views: 13521

Goodhart's law and VMC optimization.

Hello QMC people. As Goodhart's law says "When a measure becomes a target, it ceases to be a good measure". You may think that this is just a adage, but in some situations it can lead to catastrophic consequences. https://www.lesswrong.com/posts/fuSaKr6t6Zuh6GKaQ/when-is-goodhart-catastrop...
by Vladimir_Konjkov
Thu Nov 09, 2023 5:35 am
Forum: The CASINO program
Topic: Calculation of forces in QMC
Replies: 15
Views: 44991

Re: Calculation of forces in QMC

I discovered that local pseudopotentials without core electrons have been developed for H-Be, they also contain only local channel. (https://pubs.aip.org/aip/jcp/article/151/14/144110/75444/A-new-generation-of-effective-core-potentials-from). They are available on the website https://pseudopotential...
by Vladimir_Konjkov
Wed Nov 01, 2023 12:21 pm
Forum: The CASINO program
Topic: Problem with pseudopotential transformation
Replies: 4
Views: 22706

Re: Problem with pseudopotential transformation

I tried converting the pseudopotential as described above. Using: B Small Core DF AREP (Trail & Needs) 5.0 3.0 3 8 8 8 Vs - Vd 6.08975909 24273.45582357 0 6.22754424 -24267.33981731 0 7.95360685 1449.36679089 1 5.26256053 -22823.91537604 1 5.07697261 21374.54858515 1 14.04620763 -256.36140271 2 ...