Hi Giacomo,

Gotcha! Thanks for the thorough explanation. Using the Chromium example from the website (https://tutorials.crystalsolutions.eu/tutorials/soc/Cr3_so_colu_fmix.d12) I think it is straightforward to do the conversion to CRYSTAL.

One final question, if I may. Should I add:

TWOCOMPON
SOC
ENDtwo

at the beginning or at the end of the SCF block, or it does not matter?

Chris

Hi Giacomo,

Thanks for your quick reply!

I see. So for the elements I'm interested in (Nickel and Cobalt) the "pob-DZVP" and "pob-TZVP" should be all I need for an SOC calculation, right? Since they are double- and triple-zeta valence + polarization enabled.

Chris

Hi,

I am curious if Crystal accepts something like the cc-pVDZ-DK Gaussian basis set for the calculation of SOC effects in transition metals? From what I gather, it is an all electron basis set (https://www.basissetexchange.org/basis/cc-pvdz-dk/format/crystal/?version=0&elements=28). Would this require the keyword INPSOC in the basis set block of the input file?

Chris

Hi Giacomo,

That's a very useful answer, thank you!

Chris

Hello all. I have a question about CRYSTAL23 and how it works when it comes to calculating eigenvalues for certain k-points. Let's look at the example of SiO2 cell with 12 ions:

*** K POINTS COORDINATES (OBLIQUE COORDINATES IN UNITS OF IS = 6)
1-R( 0 0 0) 2-C( 1 0 0) 3-C( 2 0 0) 4-R( 3 0 0)
5-C( 1 1 0) 6-C( 2 1 0) 7-C( 2 2 0) 8-C( 0 0 1)
9-C( 1 0 1) 10-C( 2 0 1) 11-C( 3 0 1) 12-C( 1 1 1)
13-C( 2 1 1) 14-C( 2 2 1) 15-C( 0 0 2) 16-C( 1 0 2)
17-C( 2 0 2) 18-C( 3 0 2) 19-C( 1 1 2) 20-C( 2 1 2)
21-C( 2 2 2) 22-R( 0 0 3) 23-C( 1 0 3) 24-C( 2 0 3)
25-R( 3 0 3) 26-C( 1 1 3) 27-C( 2 1 3) 28-C( 2 2 3)

So here it shows 28 k-points for the 6x6x6 Monkhorst-Pack grid, and if I understand correctly, the reason why it's not showing all 216 points is because the program recognizes the crystal symmetry so it knows that the energy at (1 0 0) is the same as at (0 1 0), (0 0 1), (-1 0 0), etc?

If that is the case, then to build a high-symmetry path along Gamma-X-K-Gamma, for example... we could just take the points 4-R( 3 0 0) and 7-C( 2 2 0) and divide them by IS, which in this case is 6 to get the points (0.5, 0, 0) and (1/3, 1/3, 0). Would that be correct? Because that would make the extraction of eigenvalues quite simple for this path.

Thanks in advance,

Chris