3.3.24. POLY_ANISO — Semi-ab initio Electronic Structure and Magnetism of Polynuclear Complexes Program¶
The program POLY_ANISO calculates nonperturbatively the temperature- and field- dependent magnetic
properties (Van Vleck susceptibility tensor and function, molar magnetization vector and function) and the
pseudospin Hamiltonians for Zeeman interaction (the
For a proper spin-orbit calculation the relativistic basis sets should be used for the whole calcualtion. For SEWARD, the atomic mean-field (AMFI), Douglas–Kroll (DOUG) must be employed. To ensure the computation of angular momentum integrals the ANGMOM should be also used, specifying the origin of angular momentum integrals as the coordinates of the magnetic center of the molecule, i.e. the coordinates of the atom where the unpaired electrons mainly reside. For program RASSI the necessary keywords are: SPIN, since we need a spin-orbit coupling calculation, and MEES, to ensure the computation of angular momentum matrix elements in the basis of spin-free states (SFS).
In the cases where spin-orbit coupling has a minor effect on the low-lying energy spectrum (most of the
isotropic cases:
&POLY_ANISO
In the cases when spin-orbit coupling play an important role in the low-lying energy spectrum, i.e. in the cases of e.g. octahedral
&POLY_ANISO
MLTP
1
2
POLY_ANISO has implemented pseudospins:
&POLY_ANISO
MLTP
3
2 4 2
For the above input example, the POLY_ANISO will compute the
3.3.24.1. POLY_ANISO Output¶
The POLY_ANISO section of the Molcas output is divided in four parts. In the first part, the
In the second part, the paramaters of the crystal field acting on the ground atomic multiplet of lanthanides are calculated.
In the third part, the powder magnetic susceptibility is printed, followed by the magnetic susceptibility tensors with and without intermolecular interaction included.
In the fourth part, magnetization vectors (if required) are printed, and then the powder molar magnetization calculated for the TMAG temperature.
The keywords TINT and HINT control the temperature and field intervals for computation of magnetic susceptibility and molar magnetization respectively. Computation of the magnetic properties at the experimental temperature and field points with the estimation of the standard deviation from experiment is also possible via TEXP, defining the experimental temperature and measured magnetic susceptibility and HEXP, defining the experimental field and averaged molar magnetization.
&POLY_ANISO
TITLE
g tensor and magnetic susceptibility
TYPE
4
MLTP
2
3 3
TINT
0.0 100 101 0.001
The above input requires computation of the parameters of two pseudospins
3.3.24.2. POLY_ANISO — Basic and Most Common Keywords¶
- MLTP
Specifies the number and dimension of the pseudospins Hamiltonians
- TMAG
Sets the temperature for the computation of molar magnetization
- MVEC
Number and radial coordinates of directions for which the magnetization vector will be computed