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Amber

Member

Registered: 2025-01-22

Posts: 2

Get highly anisotropic crystal field solution for Gd3+

Hi Molcas Users:

Recently I came across a problem when calculating magnetic properties of Gd3+ monomer compound. Single_Aniso gave me a highly anisotropic solution, which makes no sense for Gd3+. The Extended Steven's Coefficients looks like this:

The Crystal-Field Hamiltonian:

   Hcf = SUM_{k,q} * [ B(k,q) * O(k,q) ];

 where:
   O(k,q) =  Irreducible Tensor Operators
             defined as follows:

          Y(k,q)             CG(J,M2,k,q,J,M1)
 < J,M1 | ------ | J,M2 >  = -----------------
          Y(k,0)              CG(J,J,k,0,J,J)

  CG - Clebsh-Gordan Coefficient:
                            c,gm
      CG(a,al,b,bt,c,gm) = C
                            a,al,b,bt

   k - the rank of the ITO, = 2, 4, 6, 8, 10, 12.
   q - the component of the ITO, = -k, -k+1, ... 0, 1, ... k;
-----------------------------------------------------------|
  k |  q  |           Complex parameter  A(k,q)            |
----|-----|--------  Real  ------|-----  Imaginary  -------|
  2 |  -2 | +2.31941673538657E+00 +1.60142416777517E-01 *I |
  2 |  -1 | +1.15202725484807E-01 -2.29147084456340E-01 *I |
  2 |   0 | +7.32183092083654E+03 -6.34442704119892E-14 *I |
  2 |   1 | -1.15202725484807E-01 -2.29147084456339E-01 *I |
  2 |   2 | +2.31941673538657E+00 -1.60142416777516E-01 *I |
----|-----|----------------------|-------------------------|
  4 |  -4 | -1.20399620053439E-02 +6.98326821694193E-03 *I |
  4 |  -3 | +3.71027797146703E-02 -1.01639792616583E-02 *I |
  4 |  -2 | -5.20582182015198E-01 -3.86012279193471E-02 *I |
  4 |  -1 | +5.25280618069196E-02 -1.13363210058462E-01 *I |
  4 |   0 | +2.07957128420868E+03 +6.18897642642590E-16 *I |
  4 |   1 | -5.25280618069202E-02 -1.13363210058463E-01 *I |
  4 |   2 | -5.20582182015199E-01 +3.86012279193472E-02 *I |
  4 |   3 | -3.71027797146702E-02 -1.01639792616582E-02 *I |
  4 |   4 | -1.20399620053438E-02 -6.98326821694194E-03 *I |
----|-----|----------------------|-------------------------|
  6 |  -6 | -2.00069246683646E-07 +1.18250088078795E-07 *I |
  6 |  -5 | +2.62153578696794E-06 -1.18020013490337E-06 *I |
  6 |  -4 | +1.77404983733096E-03 -1.04278802245838E-03 *I |
  6 |  -3 | -1.05723361838977E-02 +3.28481278156174E-03 *I |
  6 |  -2 | -3.50198324018526E-02 -2.57291597532398E-03 *I |
  6 |  -1 | +2.66529682748496E-03 -8.36742405197289E-03 *I |
  6 |   0 | +9.90949528816573E+01 -2.85310026845302E-16 *I |
  6 |   1 | -2.66529682748479E-03 -8.36742405197266E-03 *I |
  6 |   2 | -3.50198324018523E-02 +2.57291597532388E-03 *I |
  6 |   3 | +1.05723361838976E-02 +3.28481278156171E-03 *I |
  6 |   4 | +1.77404983733095E-03 +1.04278802245838E-03 *I |
  6 |   5 | -2.62153578696794E-06 -1.18020013490338E-06 *I |
  6 |   6 | -2.00069246683194E-07 -1.18250088079700E-07 *I |
-----------------------------------------------------------|

Have anyone comes across similar problem before?

Amber

Last edited by Amber (2025-01-22 19:18:15)

Amber

Member

Registered: 2025-01-22

Posts: 2

Re: Get highly anisotropic crystal field solution for Gd3+

Some additional notes:

I did the same calculation for another Gd3+ compound a few years ago, and that one gives me the result of spherical symmetry. I checked the input files of both Gd3+ calculations, line by line, to identify any possible reasons. It seems like in this problematic one, I set "MaxOrb=1" for RASSCF calculations before the Single Aniso, while in the good one I did not set anything for MaxOrb. Is it possible that this setting triggered anything that causes my problem? Though it does not seem very obvious to me...

Amber