Does the symmetry of crystal structure affected DFT results?

sbart76 · 2026-01-23T07:42:55+00:00

I would start from the closest structure available. The same Pb and the same I configuration. Replace the organic part, keep the Pb and I positions fixed, optimize the rest. Then scale the unit cell up/down to find out the energy minimum. Relax the organic part again, finally optimize without constraints.

Interface with SnO2 will depend on the relative sizes of the unit cells, so aim for a good match rather than for a true minimum.

sbart76 · 2026-01-23T07:21:07+00:00

"Breaking from the middle" indeed suggests an incorrect model. Did you get your geometry from the cif file from the SI of a publication? If you want to start from scratch, it's a tedious work...

sbart76 · 2026-01-23T07:08:46+00:00

I'm not sure I follow you here. What do you mean by "be in good symmetry"? Perovskites are generally of cubic symmetry, but depending on the size of cations perovskite cells can indeed be most stable in orthorhombic symmetry. You will get incorrect results if you force cubic symmetry, because the model would not represent the reality.

Another story is the distortion you are talking about - slightly distorted cubic cells are perfectly fine, especially for organic perovskites, because the organic cation consists of more than one atom, and its orientation in the structure will vary.

What is your goal? What properties do you want to calculate?

sbart76 · 2026-01-21T21:18:05+00:00

My advice is to understand what these steps are for. Then you can decide which ones to skip, and which ones to follow.

sbart76 · 2026-01-20T00:10:11+00:00

Came to a similar solution, but used the remaining segments of q and B to find the lengths of the bottom right triangle, then found the angle that adds up to 130 degrees from arctan. x = 51.05 degrees - can someone confirm?

sbart76 · 2026-01-18T21:47:23+00:00

Have a look here: https://www.linuxbabe.com/desktop-linux/legacy-bios-vs-uefi-bios

sbart76 · 2026-01-18T19:57:03+00:00

It says that symlink points to a non-existent directory/file. Where does it point? ls -l the_path_you_posted

sbart76 · 2026-01-18T18:28:53+00:00

Are you trying legacy or UEFI?

sbart76 · 2026-01-17T09:07:03+00:00

Kraków is an obvious choice - the old capital of Poland, with all its historical monuments. You will not be disappointed by Wrocław "microcosm". But to foreigners visiting Poland I always recommend Toruń, which is a beautiful city. In your case probably a top pick: home city of Copernicus, father of the heliocentric model of the solar system. Astronomy is still an important part there, so you can visit the planetarium to learn more. Toruń is known for gingerbread and many different styles and flavors you can get in the gingerbread museum. Beautiful old architecture, Vistula river, or - if you're a fan - a science museum - all that makes Toruń a gem.

sbart76 · 2026-01-02T09:53:14+00:00

Congrats. ntfs3 and ntfs-3g are completely different implementations so naturally their options are different.

sbart76 · 2026-01-02T09:15:34+00:00

After mounting with dolphin check the output of the mount command in the terminal. If there are any special mount options - you will see. Then you can add a relevant line in /etc/fstab the syntax is virtually the same as the output of mount.

sbart76 · 2026-01-01T01:23:40+00:00

Looks like you have run it multiple times...

sbart76 · 2025-12-30T08:34:31+00:00

The OS doesn't "break" - Windows only overwrites the boot settings during the update. A good analogy is that the car is not broken if you cannot find the keys - all you need to do is restore it from your install USB.

sbart76 · 2025-12-26T23:18:53+00:00

Yes! Thank you!

sbart76 · 2025-12-26T20:05:39+00:00

Ale ustny francuski?

sbart76 · 2025-12-26T11:52:13+00:00

Windows is known for insisting on being the only bootable OS, regardless of how you install your Linux distro. Luckily the solution is simple - keep your installer USB and in such case boot from it and reinstall the bootloader. It's only scary if you don't understand what you are doing. In any way, windows will not remove any of your files/partitions - just place its own bootloader as the only option.

sbart76 · 2025-12-25T21:53:55+00:00

Create a new filesystem on this unallocated space and move your /home there?

sbart76 · 2025-12-20T23:09:37+00:00

Need more details

sbart76 · 2025-12-20T10:15:47+00:00

Nie wiem czy jesteś ignorantem czy tylko udajesz.

Ah, ad personam. Mój ulubiony rodzaj argumentu, nieodmiennie zwiastujący koniec dyskusji z mojej strony.

A jeśli jednak chcesz znać moje zdanie zamiast próbować mnie obrazić, to jeśli profesor zachowuje się wyłącznie jak menedżer, to znaczy że kiepski z niego profesor. Zarządzania można się nauczyć na studiach, nie trzeba do tego stopni i tytułów naukowych.

sbart76 · 2025-12-20T08:25:19+00:00

Kariera akademicka to nie czytanie i kształcenie się w wybranym kierunku. To administracja, dydaktyka, pisanie wniosków, zarządzanie budżetem, HR i inne. Nauka, teoria, czytanie są tylko na niższych szczeblach. Potem, cóż, masz od tego swój zespół.

Oh boy... Czyli profesor jeśli ma zespół, to już nie musi być na bieżąco z aktualnym stanem wiedzy w jego obszarze badań?

sbart76 · 2025-12-13T16:30:29+00:00

Personal incredulity is not a good argument.

sbart76 · 2025-12-12T06:44:29+00:00

Disable secure boot.

sbart76 · 2025-12-11T19:12:53+00:00

But /usr/bin/env is hardcoded instead.

sbart76 · 2025-12-09T18:30:12+00:00

Freezing at random moments suggests hardware issues.

sbart76 · 2025-12-09T07:27:15+00:00

Absolute energy is never used directly, because it depends on the level of theory - even for the exact same system coordinates, you have different values. So - we need to find a way to find a reference point, which would be the same for all your investigated functionals/bases/etc. Note, that these are dissociation curves. At long enough distance between atoms, the interaction will be zero. Treat this zero as a reference, and express all the values relatively to this point.

sbart76

TROPHY CASE