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** Re^4: Coulomb integrals in the basis of molecular orbitals **
Dmitry

dmitry.ryndyk@physik.uni-regensburg.de

Hi,Thank you for the answer. Unfortunately, I supposed something like that.

I need two-electron integrals only for a part of molecular orbitals, in some cases only for several, but all 2-e integrals in AO basis are necessary to calculate it. The easier way will be to find real-space molecular orbitals and calculate Coulomb integral directly for that.

Best,

Dmitry

On Mon Dec 13 '10 9:43pm, Alex Granovsky wrote

----------------------------------------------

>Hi,

>what you need are the so-called transformed two-electron integrals.

>They are obtained as result of four-index transformation of

>2-e integrals in AO basis. Do you need them all at once?

>They are typically stored in binary files in packed form,

>so there is no easy way to get them printed out, esp. for

>large molecules.

>Regards,

>Alex Granovsky

>

>

>On Sat Dec 11 '10 8:32pm, Dmitry wrote

>--------------------------------------

>>Hallo,

>>I need matrix elements of the Coulomb operator $1/|r-r'|$ for 4 arbitrary molecular wave functions.

>>In the moment I can calculate Coulomb and exchange integrals for 2 arbitrary functions using localization run with "local=ruednbrg", but possibly it is easier way.

>>Sincerely,

>>Dmitry

>>

>>

>>On Sat Dec 11 '10 8:01pm, Alex Granovsky wrote

>>----------------------------------------------

>>>Hi,

>>>do you need the transformed two-electron integrals or rather

>>>matrix elements of the Coulomb operator?

>>>Regards,

>>>Alex Granovsky

>>>On Sat Dec 11 '10 10:16am, Dmitry wrote

>>>---------------------------------------

>>>>Please, suggest how one can calculate the Coulomb integrals in the basis of arbitrary set of molecular orbitals, given in $vec group?

Mon Dec 13 '10 11:30pm

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