At [1], I came across slide 100 having "Practical 5: Hysteresis simulations".
I also came across the Vampire files at [2,3]. The files at [2] seem to have placeholders to enter different parameter values so that a user can adjust them to see what they do.
I combined things from [1-4], and then, I was just fiddling around with the files putting different values such that a few of the values may be unrealistic which resulted in the attached input and Ni.mat files. However, it did output a plot that looks like a hysteresis loop, as shown in the attached Ni.png, if it is of interest to you where the calculation was ran in a terminal using:
username@computername:~/Ni$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04.3 LTS
Release: 20.04
Codename: focal
username@computername:~/Ni$ ls -l
total 8
-rw-r--r-- 1 username username 1514 Aug 20 05:29 input
-rw-r--r-- 1 username username 847 Aug 19 23:29 Ni.mat
username@computername:~/Ni$ vampire-serial
_
(_)
__ ____ _ _ __ ___ _ __ _ _ __ ___
\ \ / / _` | '_ ` _ \| '_ \| | '__/ _ \
\ V / (_| | | | | | | |_) | | | | __/
\_/ \__,_|_| |_| |_| .__/|_|_| \___|
| |
|_|
Version 5.0.1 Jul 19 2021 05:54:31
Git commit: c0cb858d7dcdcdfc6474938324e363599e728b30
Licensed under the GNU Public License(v2). See licence file for details.
Lead Developer: Richard F L Evans <richar...@york.ac.uk>
Contributors: Andrea Meo, Rory Pond, Weijia Fan,
Phanwadee Chureemart, Sarah Jenkins, Joe Barker,
Thomas Ostler, Andreas Biternas, Roy W Chantrell,
Wu Hong-Ye, Matthew Ellis, Razvan Ababei,
Sam Westmoreland, Oscar Arbelaez, Sam Morris
Compiled with: GNU C++ Compiler
Compiler Flags:
Vampire includes a copy of the qhull library from C.B. Barber and The
Geometry Center and may be obtained via http from www.qhull.org.
================================================================================
Fri Aug 20 22:10:51 2021
================================================================================
Initialising system variables
Creating system
Generating neighbour list..........done!
Copying system data to optimised data structures.
Using generic/normalised form of exchange interaction with 48 total interactions.
Number of atoms generated: 6084
Starting Simulation with Program Hysteresis-Loop...
Simulation run time [s]: 3472.06
Simulation ended gracefully.
username@computername:~/Ni$ gnuplot
G N U P L O T
Version 5.2 patchlevel 8 last modified 2019-12-01
Copyright (C) 1986-1993, 1998, 2004, 2007-2019
Thomas Williams, Colin Kelley and many others
gnuplot home: http://www.gnuplot.info
faq, bugs, etc: type "help FAQ"
immediate help: type "help" (plot window: hit 'h')
Terminal type is now 'wxt'
gnuplot> set xlabel "Applied field (T)"
gnuplot> set ylabel "m_z"
gnuplot> p "output" u 2:5 w p