Centrosymmetry Parameter

Measure local centrosymmetry as a fast way to highlight disorder and defect-rich regions.

Overview

Centrosymmetry Parameter is a classic defect-visualization tool. It gives each atom a scalar value that grows as the local environment becomes less centrosymmetric, which makes it especially useful for surfaces, defect cores, and distorted crystalline regions.

It is best used as a highlighting metric rather than as a full defect classifier. The output tells you where local symmetry is breaking down, and you decide how to interpret that in the context of the system.

Parameters

Parameter	Type	Default	Description
`numNeighbors`	`int`	`12`	Number of nearest neighbors to consider. Use a value consistent with the lattice you expect.
`mode`	`string`	`conventional`	CSP calculation mode. Options: `conventional`, `matching`.

Practical notes

The plugin always emits a histogram summary alongside per-atom CSP values.
The histogram currently uses a fixed number of bins in the implementation.
Atoms with too few neighbors for the requested calculation are emitted with 0.0, which matters near surfaces or in sparse regions.

Output

`{outputBase}_centrosymmetry.msgpack`

interface PerAtomProperties {
    id: int;
    csp: float;
}

interface CentrosymmetryOutput {
    main_listing: {
        total_atoms: int;
        histogram_bins: int;
        histogram_bin_size: float;
        max_csp: float;
        histogram_counts: int[];
        histogram_interval: {
            start: float;
            end: float;
        };
    };
    "per-atom-properties": PerAtomProperties[];
}