Molcas Forum

Sihan Zhang

Member

Registered: 2025-05-15

Posts: 10

RASSI Dipole Transition Intensity

I am now calculating the CeO8 cluster in EBM. After the the RASSCF calculation, I asked the RASSI>TRDI to give me the transition intensity, but they were not printed out and the programs said "No problematic oscillator strengths above the tolerance have been found". Could you please help me to check the problem. And also one additional questions, is there any way to print quadrupole transition intensities by one key work instead of asking for the transition eigenvalue matrixes.

The RAS1 is 2p, RAS2 is ligand orbitals, RAS3 is 5d

&RASSCF
  Spin = 1
  HEXS = 1; 1
  Symmetry = 2
  NActEl    * Nel, h RAS1, n RAS3
    14 1 1
  LUMORB    * Read Orb from INPORB
  TypeIndex    * Read OrbType from INPORB
  CIRoot = 48 48 1    * NRoots NDacidsons
  Iter
    200 100
  OrbListing    * List all Orbs
    All
  OrbAppear    * OrbList Print Level
    Compact
  SupSym
    0
    1; 1 1
    1; 1 1
    1; 1 6
    1; 1 1  
    1; 1 6
    1; 1 6
    1; 2 5 6 
End of Input

>> COPY $Project.JobIph $CurrDir/$Project.EXC.JobIph

>> COPY $CurrDir/$Project.GS.JobIph JOB001
>> COPY $CurrDir/$Project.EXC.JobIph JOB002

&RASSI
  SpinOrbit    * SOC Calc
  Nr of JobIphs    * Input States
    2 All
  SubSets = 2
  TRDI
End of Input

Last edited by Sihan Zhang (2025-05-16 11:46:47)

Ignacio

Administrator

From: Uppsala

Registered: 2015-11-03

Posts: 1,203

Re: RASSI Dipole Transition Intensity

According to the documentation:

TRDI

    Prints out the components and the module of the transition dipole vector. Only vectors with sizes large than 1.0D-4 a.u. are printed. See also the TDMN keyword.

You probably want to use the keywords TDMN and/or DIPR.

For the quadrupole transitions, try QIAL and QIPR

Sihan Zhang

Member

Registered: 2025-05-15

Posts: 10

Re: RASSI Dipole Transition Intensity

I tried all of them, even reduce the TDMN to 1.0D-10, still not working. I initially thought it is an input file or version problem, so i just tried the same calculation for CeF6, and got some intensities.

Ignacio

Administrator

From: Uppsala

Registered: 2015-11-03

Posts: 1,203

Re: RASSI Dipole Transition Intensity

Maybe they're zero? Try with zero (or negative) thresholds.

Sihan Zhang

Member

Registered: 2025-05-15

Posts: 10

Re: RASSI Dipole Transition Intensity

Actually, they are not zero. I later asked for the input file from one paper author. I noticed that it was because of the keywork Symmetry in RASSCF. I need to give a corresponding symmetry of the transition. Then I can get the intensity. I know how to solve it, but still curious about what happened behind.

hunghv

Member

Registered: 2026-02-26

Posts: 5

Re: RASSI Dipole Transition Intensity

I faced with the same problem.

Could you please give me more detail about your solutions?

Sihan Zhang

Member

Registered: 2025-05-15

Posts: 10

Re: RASSI Dipole Transition Intensity

I faced with the same problem.

Could you please give me more detail about your solutions?

I put my files here.

&RASSCF
  Spin = 1
  Symmetry = 5
  HEXS = 1; 1
  NActEl
    8 1 1
  LUMORB
  TypeIndex
  CIRoot = 16 16 1
  ....
End of Input

&RASSI
  SpinOrbit 
  Nr of JobIphs 
    3 All
  SubSets = 3  
  EJob
  DIPrint = 1.0D-8 
End of Input

If you defined the symmetry, then you need to specify the state symmetry in RASSCF module, or it will calculate on the default value 1. This can be forbidden by the selection rule depends on the symmetry. For example, my system is in Oh symmetry (C2h in Molcas), ground state is 1 (Ag), excited states are 2/3/5 (B1/2/3u). This is allowed by dipole selection rule.

Last edited by Sihan Zhang (2026-02-28 23:07:15)

hunghv

Member

Registered: 2026-02-26

Posts: 5

Re: RASSI Dipole Transition Intensity

Thanks

Could you please give me more detail about Symmetry =5 in your inout. How can I know the Symmetry?

I have tried Symmetry= from 1 to 8 in my inout, but it did not help.

Below is my input.

###################################

&GATEWAY
COORD
3

C   0.0000000000  0.0000000000  0.0000000000
O1  0.0000000000  0.0000000000 -1.1620000000
O2  0.0000000000  0.0000000000  1.1620000000
BASIS=cc-pVTZ	
GROUP=FULL
AMFI
&SEWARD
&SCF
&RASSCF
GUGA
SPIN=1
CIROOT=18 18 1
Inactive = 4  1  1  0 2  1  1  0
Ras2     = 5  5  5  2 15 4  4  2
Symmetry=1
&RASSI
TDMN
1.0D-8
Nr of JobIphs 
1 ALL

##########################################

Sihan Zhang

Member

Registered: 2025-05-15

Posts: 10

Re: RASSI Dipole Transition Intensity

Thanks

Could you please give me more detail about Symmetry =5 in your inout. How can I know the Symmetry?

I have tried Symmetry= from 1 to 8 in my inout, but it did not help.

Below is my input.

1. See this link https://molcas.gitlab.io/OpenMolcas/sph … teway.html

You didn't define the symmetry, therefore, the irrep notation can not work. You can modify in this way:

Suppose you need to calculate in D2h, since I saw you use 8 irreps in the RASSCF module.

COORD
3
C   0.0000000000  0.0000000000  0.0000000000
O1  0.0000000000  0.0000000000 -1.1620000000
SYMMETRY = X Y Z

The second O can be generated by the symmetry.

2. Do calculations in two different irreps. You use RASSI directly after the RASSCF, there is only the states of Ag irrep. The dipole transition between them us forbidden. You need run two calculations for Ag and B1/2/3u to obtain the transition by reading their JobIph/JobMix files, or other irrep combination depending on the state symmetry and tensor product table.

These are carefully written in the manual:
https://molcas.gitlab.io/OpenMolcas/sph … ex-ex.html

Last edited by Sihan Zhang (2026-03-01 17:10:02)

hunghv

Member

Registered: 2026-02-26

Posts: 5

Re: RASSI Dipole Transition Intensity

Thank you very much Sihan Zhang