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lcadi

Member

Registered: 2022-09-29

Posts: 1

Smaller Symmetry Yield Significant CF in Ln(III) RASSCF calculation

Hello, everyone

I am a researcher from Osaka University - Japan and currently I am working on trivalent lanthanide or Ln(III) complexes. I am also a new MOLCAS user and recently, I am conducting ground state RASSCF calculation with basis set ANO-RCC-VTZP for the complex of Dy-Porphyrin-12Crown4 ether in a sandwich structure where Dy is in between Porphyrin and the crown ether.
I used two molecular symmetries here: C1 and C2. However, I obtain very contrasting results. For C1 symmetry, the lowest spin-orbit state is |+ 15/2> with this specificity:

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
     CALCULATION OF PSEUDOSPIN HAMILTONIAN TENSORS FOR THE MULTIPLET 1 ( effective S =  1/2)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
The pseudospin is defined in the basis of the following spin-orbit states:
spin-orbit state 1. energy(1) =       0.000 cm-1.
spin-orbit state 2. energy(2) =       0.000 cm-1.
Tunnelling splitting:     0.0000000000 cm-1.

    g TENSOR:
--------------------------------------------------------|
    MAIN VALUES    |             MAIN MAGNETIC AXES     |   x , y , z  -- initial Cartesian axes
-------------------|----|----- x ------- y ------- z ---|   Xm, Ym, Zm -- main magnetic axes
 gX =   0.00091877200123 | Xm |  0.00000010816103  0.00000179921922  0.99999999999838 |
 gY =   0.00146914249603 | Ym |  0.04451203509995  0.99900884817303 -0.00000180225038 |
 gZ =  19.73760015282768 | Zm | -0.99900884817465  0.04451203510008  0.00000002796692 |
--------------------------------------------------------|
CHECK-SIGN parameter =   -3.445076
The sign of the product gX * gY * gZ for multiplet 1: < 0.

While when C2 symmetry is used, the lowest spin-orbit state is |+ 11/2> with the description below.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
     CALCULATION OF PSEUDOSPIN HAMILTONIAN TENSORS FOR THE MULTIPLET 1 ( effective S =  1/2)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
The pseudospin is defined in the basis of the following spin-orbit states:
spin-orbit state 1. energy(1) =       0.000 cm-1.
spin-orbit state 2. energy(2) =       0.000 cm-1.
Tunnelling splitting:     0.0000000000 cm-1.

    g TENSOR:
--------------------------------------------------------|
    MAIN VALUES    |             MAIN MAGNETIC AXES     |   x , y , z  -- initial Cartesian axes
-------------------|----|----- x ------- y ------- z ---|   Xm, Ym, Zm -- main magnetic axes
 gX =   1.13705083805391 | Xm |  0.99582237436236  0.09131154756831  0.00000000000000 |
 gY =   1.13706002810245 | Ym | -0.09131154756831  0.99582237436236  0.00000000000000 |
 gZ =  13.79316827036589 | Zm |  0.00000000000000  0.00000000000000  1.00000000000000 |
--------------------------------------------------------|
CHECK-SIGN parameter =    3.468962
The sign of the product gX * gY * gZ for multiplet 1: > 0.

Theoretically, the complex has a high molecular symmetry and C2 is more suitable than C1. Nonetheless, in C2, the gZ tensor is located in axial position along  z-axis, in contrary with the gZ tensor obtained in C1 symmetry in which in the latter the gZ tensor is on equatorial position. Would you please explain why such very significant results were obtained? Also, is it possible to turn Zm value resulted by C1 symmetry from x-axis to z-axis?

Thank you very much for your help.

Last edited by lcadi (2022-10-03 01:47:49)

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Dr. Langit Cahya Adi
Graduate School of Science
Osaka University - Japan