Dear Dalton Community,
My name is Vsevolod, nice to meet you. I am interested in variation of electron mass and electron charge constants to observe any structural changes of some selected compounds. For that, I need to modify 1 and 2electron integrals of SCF procedure and need some help on this way.
If not mistaken, I have already found 1electron potential (POTINT) and kinetic energy (KININT) integrals in DALTON/abacus/her1int.F.
However, I am still struggling with 2electron Vee term (Coloumb and Exchange) and Vnn term as average of nuclear repulsion.
Could you please help me find those integrals in the source code?
Or, if it is easier, to show how to modify respective 1 and 2electron parts of the Fock matrices.
Thank you,
Seva
Modifying SCF integrals

 Posts: 334
 Joined: 27 Jun 2013, 18:44
 First name(s): Hans Jørgen
 Middle name(s): Aagaard
 Last name(s): Jensen
 Affiliation: Universith of Southern Denmark
 Country: Denmark
Re: Modifying SCF integrals
Well ... If
to
and in
to
I think this will do what you want. If I understand you correctly, the Vnn term should not be changed becuase it does not depend on the electron mass nor on the electron charge.
m_factor
is the electronic mass factor and e_factor
is the factor on the electronic charge, I think the easiest is to modify the lines where the oneelectron Hamiltonian is constructed by adding the kinetic energy integrals and the nuclear attraction integrals in .../DALTON/abacus/her1drv.F
, that is, change
Code: Select all
DO 800 I = 1, NNBAST
STHMAT(I,2) = STHMAT(I,2) + STHMAT(I,3)
800 CONTINUE
Code: Select all
DO 800 I = 1, NNBAST
STHMAT(I,2) = STHMAT(I,2)/m_factor + STHMAT(I,3)*e_factor
800 CONTINUE
.../DALTON/sirius/sirgrad.F
change in subroutine FCK2AO (which calculates the twoelectron contribution to the Fock matrix):
Code: Select all
C
C *** End of subroutine FCK2AO
C
CALL QEXIT('FCK2AO')
RETURN
END
Code: Select all
C
C *** End of subroutine FCK2AO
C
e2_factor = e_factor**2
call dscal(ndmat*n2basx,e2_factor, FCAO, 1)
CALL QEXIT('FCK2AO')
RETURN
END

 Posts: 2
 Joined: 07 Oct 2019, 00:32
 First name(s): Vsevolod
 Last name(s): Dergachev
 Affiliation: University of Nevada, Reno
 Country: United States
Re: Modifying SCF integrals
Dr. Jensen,
Thank you very much.
Thank you very much.
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