Molcas Forum

ruslan

Member

Registered: 2020-10-29

Posts: 5

Minimun holes in core for the core-spectrum simulation

Hello, guys!
I have two questions.
1. The min. holes in RAS1
Previously I used DALTON, where I could the set the min. holes in RAS1. For example, I can insert 1s of O atom in RAS1 with the occupancy by 1. So it was minimum one hole in RAS1 with one Mo.   I can't fine this option in MOLCAS. So I need min holes value setup for RAS1 and min. values for electrons in RAS3. How can I set?

2. The transition dipole moment calculation between ground state and core-hole-state.
I want to calculate the transition dipole moment between ground zero charge state (singlet) and the core-valence state with 2 electrons removing (so, charge will be 2 with the one hole in core orbital and one in valence)... Is it possible using RASSI?
Thank you!

nikolay

Member

From: Stuttgart

Registered: 2016-03-21

Posts: 54

Re: Minimun holes in core for the core-spectrum simulation

Hello ruslan,

RASSCF module is able to perform RASSCF calculation with defined RAS1, RAS2, and RAS3. You should read the relevant manual section.

ruslan

Member

Registered: 2020-10-29

Posts: 5

Re: Minimun holes in core for the core-spectrum simulation

Hello ruslan,

RASSCF module is able to perform RASSCF calculation with defined RAS1, RAS2, and RAS3. You should read the relevant manual section.

I looked again the manual and couldn't find the keywords for holes (minimum, not max!!!). It is important to simulate the photoelectron spectra like core-hole and holes in both core and valence MOs.
Can you explain? Is it possible using the MOLCAS? In DALTON, I could it (for example
.RAS1 HOLES # elect. that may be removed from RAS1
1 1
It means every time the one hole exists in RAS1. I can freeze this orbital and simulate).

nikolay

Member

From: Stuttgart

Registered: 2016-03-21

Posts: 54

Re: Minimun holes in core for the core-spectrum simulation

I see your point only now, sorry.
HEXS keyword should do what you need.

HEXS
1            * perform one-hole restriction for one space
1            * keep one hole in the first space (RAS1)

Another option would be to properly define GASSCF.
This way you can get excited state as in resonant XAS.

Regarding the second question, you should try to run RASSI with different number of electrons.
I'm not sure it is supported.

Last edited by nikolay (2020-11-11 16:34:31)

ruslan

Member

Registered: 2020-10-29

Posts: 5

Re: Minimun holes in core for the core-spectrum simulation

I see your point only now, sorry.
HEXS keyword should do what you need.

HEXS
1            * perform one-hole restriction for one space
1            * keep one hole in the first space (RAS1)

Another option would be to properly define GASSCF.
This way you can get excited state as in resonant XAS.

Regarding the second question, you should try to run RASSI with different number of electrons.
I'm not sure it is supported.

Hello, thank you very much! GASSCf is perfect.
1) But RASPT2 with GASSCf does not work for me.
2) Dyson orbitals.... I heard there is a module for photoionization cross section (PICS) simulation. I can take Dyson orbitals using
DYSOn
DYSExport
but I can't find the external module for the (PICS) simulation. Do you know?
Thank you!