FINDSPINGROUP

findspingroup is a Python toolkit, command-line program, and web application for identifying and inspecting oriented spin space group (OSSG) symmetry in magnetic crystal structures.

It is designed for research workflows involving the interplay between exchange-driven magnetic geometry and spin-orbit coupling, which are described by spin space group (SSG) and magnetic space group (MSG) frameworks, respectively.

Given a magnetic structure, FINDSPINGROUP identifies the OSSG, derives the corresponding MSG, and organizes crystallographic and physical information needed to analyze the material with and without spin-orbit coupling.

Main outputs

Main outputs can include:

  • OSSG information and corresponding MSG information in matched settings;
  • spin Wyckoff positions and Wyckoff splitting from space group (SG) to OSSG and MSG;
  • spin Brillouin zones, high-symmetry k points, and symmetry-allowed spin-polarization components;
  • additive quasi-2D k-point and spin-splitting diagnostics for slab inputs;
  • magnetic-phase classification, including unconventional cases such as altermagnets and spin-orbit magnets;
  • symmetry constraints on anomalous Hall conductivity, nonlinear tensors, and related physical responses;
  • chiral and polar group information with and without spin-orbit coupling;
  • .scif files in public convention, database-standard, magnetic-primitive, or input-cell settings;
  • magnetic primitive-cell POSCAR files in relevant coordinate conventions;
  • compact GSPG text and operation output;
  • KPOINTS files labeled with symmetry-allowed spin-polarization components.

Quick start

from findspingroup import example_path, find_spin_group

result = find_spin_group(example_path("0.800_MnTe.mcif"))
print(result.index)
print(result.convention_ssg_international_linear)
print(result.magnetic_phase)

Next steps

  • See Installation for package installation options.
  • See Usage for MagSymmetryResult, basic summaries, and input-SSG outputs.
  • See Examples for packaged sample inputs.
  • See SCIF for .scif export and roundtrip notes.
  • See CLI for command-line entry points.