Examples#

The tutorials below cover the full pyscal API — from loading structures to computing structural descriptors.

Getting started

Loading structures with ASE, the pyscal workflow, and where results are stored.

Getting Started with pyscal

Creating structures

Built-in crystal types, elements by name, custom lattices, and grain boundaries.

Creating Structures

Finding neighbors

Cutoff (fixed / adaptive / SANN), Voronoi, and number-based neighbor methods.

Finding Neighbors

Steinhardt parameters

Bond-orientational order parameters q_l and their neighbor-averaged variants.

Steinhardt Bond-Order Parameters

Common neighbor analysis

Adaptive CNA and conventional CNA for identifying FCC, HCP, BCC, and icosahedral environments.

Common Neighbor Analysis (CNA)

Voronoi tessellation

Voronoi structure vector (n3, n4, n5, n6) and Voronoi-based neighbor finding.

Voronoi Tessellation

Disorder parameter

Quantifying structural disorder using Steinhardt parameter correlations.

Disorder Parameter

Angular & chi parameters

Angular criteria for diamond detection and Ackland-Jones chi parameters.

Angular Parameters and Chi Parameters

Centrosymmetry parameter

Detecting defects and broken symmetry in ordered crystals.

Centrosymmetry Parameter

Entropy parameter

Pair-entropy for distinguishing crystal structures, with local and averaged variants.

Entropy Parameter

Short-range order

Warren-Cowley chemical short-range order parameter for multi-component alloys.

Short-Range Order (SRO)

Solid/liquid clustering

Identifying solid atoms in a melt and clustering by arbitrary conditions.

Solid-Liquid Classification and Clustering

Trajectory module

Efficient analysis of multi-frame LAMMPS dump trajectories.

Trajectory Module

Wigner W parameters

Third-order bond-orientational invariants w_l and their averaged variants.

Wigner W_l parameters

Minkowski structure metrics

Voronoi face-area weighted Steinhardt parameters for robust structure identification.

Minkowski structure metrics

Ackland-Jones classification

Angular-distribution-based structure classification for FCC, BCC, HCP, and icosahedral.

Ackland–Jones structure classification

Coordination variants

Coordination number computed via cutoff, Voronoi, and SANN neighbor methods.

Coordination number — and its smarter cousins

Angular bond distributions

Bond-angle distribution functions for characterizing local environments.

Angular and bond-length distribution functions

Deformation descriptors

Per-atom deformation gradient, strain, and slip-vector descriptors.

Deformation descriptors

Wigner-Seitz defects

Vacancy and interstitial detection via Wigner-Seitz cell analysis.

Wigner–Seitz defect analysis

ACE descriptors

Atomic Cluster Expansion descriptors for machine-learning interatomic potentials.

ACE — Atomic Cluster Expansion descriptors