magnopy-optimize-sd

This scenario optimizes classical energy of the spin Hamiltonian and finds the spin directions that describe a local minima of the energy landscape.

Arguments of the script

To get the best description of the input parameters that correspond to the magnopy version that you have installed run the command

magnopy-optimize-sd --help

That should output something similar to

usage: magnopy-optimize-sd [-h] -sf filename -ss name [-sv [S1 S2 S3 ... ...]]
                           [-et ENERGY_TOLERANCE] [-tt TORQUE_TOLERANCE]
                           [-mf MAGNETIC_FIELD MAGNETIC_FIELD MAGNETIC_FIELD]
                           [-of OUTPUT_FOLDER]
                           [-msdi xa_1 xa_2 xa_3 xa_1 xa_2 xa_3 xa_1 xa_2 xa_3]

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██║╚██╔╝██║ ██╔══██║ ██║  ╚██║ ██║╚██╗██║ ██║   ██║ ██╔═══╝    ╚██╔╝
██║ ╚═╝ ██║ ██║  ██║ ╚██████╔╝ ██║ ╚████║ ╚██████╔╝ ██║         ██║
╚═╝     ╚═╝ ╚═╝  ╚═╝  ╚═════╝  ╚═╝  ╚═══╝  ╚═════╝  ╚═╝         ╚═╝
                                                           ▄   ▄
                      Version: 0.1.8                       █▀█▀█
                Documentation: magnopy.org                 █▄█▄█
                Release date: 26 June 2025                  ███   ▄▄
                    License: GNU GPLv3                      ████ █  █
          Copyright (C) 2023-2025  Magnopy Team             ████    █
                                                            ▀▀▀▀▀▀▀▀

This script optimizes classical energy of the spin Hamiltonian and finds the spin directions that describe a local minima of the energy landscape.

options:
  -h, --help            show this help message and exit
  -sf, --spinham-filename filename
                        Path to the spin Hamiltonian file, from where the
                        parameters would be read.
  -ss, --spinham-source name
                        Source of the spin Hamiltonian. Either "GROGU" or
                        "TB2J"
  -sv, --spin-values [S1 S2 S3 ... ...]
                        In the case when the parameters of spin Hamiltonian
                        comes from TB2J, one might want to change the values
                        of spins to be closer to half-integers. This option
                        allows that. Order of the M numbers should match the
                        order of magnetic atoms in the spin Hamiltonian. Note
                        that those numbers are always positive. To specify AFM
                        order use opposite spin directions and not spin values
                        of the opposite sign.
  -et, --energy-tolerance ENERGY_TOLERANCE
                        Tolerance parameter. Difference between classical
                        energies of two consecutive optimization steps.
  -tt, --torque-tolerance TORQUE_TOLERANCE
                        Maximum torque among all spins.
  -mf, --magnetic-field MAGNETIC_FIELD MAGNETIC_FIELD MAGNETIC_FIELD
                        Vector of external magnetic field, given in the units
                        of Tesla.
  -of, --output-folder OUTPUT_FOLDER
                        Folder where all output files of magnopy wil be saved.
  -msdi, --make-sd-image xa_1 xa_2 xa_3 xa_1 xa_2 xa_3 xa_1 xa_2 xa_3
                        Plots optimized spin directions and saves it in .html
                        file, that can be viewed within any modern browser.
                        Expects three integers as an input - the supercell
                        that will be plotted. Pass 1 1 1 to plot only the unit
                        cell.

At the very beginning there is a syntax for the usage of the script, where required arguments are given without brackets and optional arguments are written with brackets. Then there is a logo of magnopy, followed by the list of supported arguments with their short and long names and explanation of what they represent.

For example, for the filename with the parameters of the spin Hamiltonian one can use a keyword argument with short name "-sf" or with its long name "--spinham-filename" like

magnopy-optimize-sd -sf spinHamiltonian.txt

Interpretation of the output

The script print in the console the progress of the calculation. Use the stream redirect to save it to a file

magnopy-optimize-sd ... > output.txt

Some of the data and pictures will be saved in the folder with the name defined by the value of -of, --output-folder argument.