Molcas Forum

Ruebchen

Member

Registered: 2020-10-30

Posts: 1

How to decide if electronic RASSI-states are doublets (non-Kramer-ion)

Hello everyone,

I have run MOLCAS calculations for Terbium and Holmium and do not know, which energy difference is high enough to tread the two energiestates not as doublets (after RASSI-Calculation).
Does anybody has experiences with it and could tell me a value for the maximal energiegap that is okay for treating the two states as doublet (for SINGLE_ANISO-calculation)?

For example:
RASSI energies for Ho-complex (in cm⁻1):
state 1: 0.000
state 2: 1.757
state 3: 43.741
state 4: 51.676
state 5: 83.289
state 6: 88.540
state 7: 112.830
state 8: 116.966
state 9: 144.936
state 10: 166.489
state 11: 226.090
state 12: 251.961
state 13: 258.255
state 14: 269.610
state 15: 276.239
and so on...

For state 9/10 and 11 it is clear, that there are single states, but what is for example with state 1 and 2?

Thanks in advance
Jan

nikolay

Member

From: Stuttgart

Registered: 2016-03-21

Posts: 54

Re: How to decide if electronic RASSI-states are doublets (non-Kramer-ion)

Hello Jan,
states 1 and 2 are very close indeed, at 50K their occupation would be 51-49 or so. On the other hand others are not too far as well.

Though, I see a problem in taking two non-degenerate states as a doublet: there are no zero-field spin operators that can lead to such scenario.
If we have spin 1/2, the doublet can (only?) be split by magnetic field, which is can change many things.

It seems to be more reasonable to find out from which multiplets all those states arising by looking at higher symmetry case and follow the symmetry descent.
Then you will know that those single states are pieces of split larger multiplet with well defined D, E or higher-order interaction.

Last edited by nikolay (2020-11-02 10:32:39)