Re: A question regarding SAPT analysis using def2 bases

dummy@example.com (saeed_E) — Sat, 01 Mar 2025 15:02:22 +0000

Dear Tian,
Many thanks for your kind attention to prompt reply with highly valuable guidance.
So, given your nice comment, File 1 should be correct.

Moreover, I asked this question on the PSI4 forum but, unfortunately, and the same as other questions I did not receive any reply!
I also performed many searches on the net to find an appropriate response. Please be aware that the only valid file I could find regarding this question is "https://github.com/psi4/psi4/blob/maste … /input.dat". Interestingly, in quite agreement with your highly valuable recommendation, this file also uses "def2-SVP-ri" basis set as the orbital basis set is also "def2-SVP".

Once again, too many thanks.

Sincerely,
Saeed

Re: A question regarding SAPT analysis using def2 bases

dummy@example.com (sobereva) — Sat, 01 Mar 2025 13:12:46 +0000

I am not sure about def2-universal-ri, but using def2-tzvpp-ri should be the safest choice, as it was designed specifically for def2-tzvpp primary basis set.

A question regarding SAPT analysis using def2 bases

dummy@example.com (saeed_E) — Sat, 01 Mar 2025 09:59:19 +0000

Dear Tian,
I hope you are doing well and, like always, kindly let me ask a question on my problem about SAPT analysis.
Please suppose one wants to perform SAPT analysis on a dimer, including heavy elements, for which using "def2" bases is mandatory. Let us take "def2-TZVPP" as the desirable basis set for such a give analysis.
It seems in the recent versions of PSI4 one should use "def2-universal-jkfit" instead of "def2-TZVPP-jkfit". The question is:
Is it also mandatory to employ "def2-universal-ri" instead of "def2-tzvpp-ri"? In other words, which of the below input files are reasonable and should be used (As I checked, the results are somewhat different:

File 1:

memory 55 gb

molecule {
0 1
C -1.56109100 -1.20061800 -0.00000400
C -0.17334400 -1.20786600 0.00002200
C 0.50607200 -0.00007600 0.00002300
C -0.17333700 1.20786200 0.00001700
C -1.56097000 1.20068700 -0.00000300
C -2.25745700 0.00000900 -0.00001500
H -2.09690700 -2.13988300 -0.00002400
H 0.37960100 -2.13607100 0.00000800
H 0.37980500 2.13594700 0.00001000
H -2.09684600 2.13992100 -0.00001000
H -3.33850200 0.00010300 -0.00001600
Cl 2.24080100 0.00000000 -0.00001200
--
2 1
Hg -0.77409920 -0.36639646 -1.52722807

units angstrom
no_reorient
symmetry c1
}

set {
basis def2-tzvpp
df_basis_scf def2-universal-jkfit
df_basis_sapt def2-tzvpp-ri
scf_type DF
guess sad
freeze_core True
}

set_num_threads(8)

energy('sapt2')
/////////////////////////////////////
File 2:

memory 55 gb

units angstrom
no_reorient
symmetry c1
}

set {
basis def2-tzvpp
df_basis_scf def2-universal-jkfit
df_basis_sapt universal-ri
scf_type DF
guess sad
freeze_core True
}

set_num_threads(8)

energy('sapt2')
//////////////////////////////////////////////

In advance, your highly valuable guidance is very appreciated and, please excuse me for bothering you.

Sincerely yours,
Saeed