crystal_space_group calculation style
Lucas M. Hale, lucas.hale@nist.gov, Materials Science and Engineering Division, NIST.
Introduction
The crystal_space_group calculation style characterizes a bulk atomic system (configuration) by determining its space group by evaluating symmetry elements of the box dimensions and atomic position. This is useful for analyzing relaxed systems to determine if they have transformed to a different crystal structure. An ideal unit cell based on the identified space group and the system’s box dimensions is also generated.
Version notes
2018-07-09: Notebook added.
2019-07-30: Function slightly updated
2020-09-22: Setup and parameter definition streamlined. Method and theory expanded.
2022-03-11: Notebook updated to reflect version 0.11.
Additional dependencies
Disclaimers
The results are sensitive to the symmetryprecision parameter as it defines the tolerance for identifying which atomic positions and box dimensions are symmetrically equivalent. A small symmetryprecision value may be able to differentiate between ideal and distorted crystals, but it will cause the calculation to fail if smaller than the variability in the associated system properties.
Method and Theory
The calculation relies on the spglib Python package, which itself is a wrapper around the spglib library. The library analyzes an atomic configuration to determine symmetry elements within a precision tolerance for the atomic positions and the box dimensions. It also contains a database of information related to the different space groups.
More information can be found at the spglib homepage.