Version 1.1

Version 1.1 adds support for multiple input file formats (LAMMPS dump, LAMMPS data, Extended XYZ, VASP POSCAR/CONTCAR, CIF, and AtomEye extended CFG), triclinic periodic cells, automated filter generation from crystal structures (-mf), and EPS image output for 2D systems.

VoroTop code and installation instructions can be obtained from the VoroTop git repository. Note that VoroTop requires the dev branch of the Voro++ library.

Please see the VoroTop Tutorial Through Examples for hands-on lessons for learning how to use VoroTop. Through carefully designed examples, you will learn to perform various types of Voronoi topology analysis, starting from basic calculations to more advanced techniques.

An implementation of VoroTop is available in OVITO.

Download from GitHub Tutorial
Filters

Filters specify sets of Voronoi topologies associated with particular structure types. Each filter is stored in a text-based format. Structure types are listed first, and are labeled with increasing integer values starting at 1. Subsequent lines specify topological types (as recorded through Weinberg vectors) and their associated structure types.

Below are filters for several common structure types. A larger collection of filters for 779 materials from the Materials Project is available in the Filter Library. Users can also generate their own filters from crystal structures using the -mf option in VoroTop, or use VoroTypes to deterministically enumerate all possible Voronoi cell topologies for a given crystal structure.

Filter name Structure Notes
BCC 1BCC Identifies particles with body-centered cubic (BCC) local structure; ignores all other structure types.
FCC 1FCC Identifies particles with face-centered cubic (FCC) local structure; ignores all other structure types.
HCP 1HCP Identifies particles with hexagonal close-packed (HCP) local structure; ignores all other structure types.
ICOS 1ICOS Identifies particles with icosahedral local structure; ignores all other structure types.
FCC-HCP 1
2
FCC
HCP (non-FCC)
Designed for studying FCC systems with HCP-type defects (e.g., dislocation, twin planes, and stacking faults).
HCP-FCC 1
2
HCP
FCC (non-HCP)
Designed for studying HCP systems with FCC-type defects (e.g., dislocation, twin planes, and stacking faults).
FCC-both-HCP 1
2
3
FCC
FCC/HCP
HCP
Designed to study systems with both FCC and HCP local structure.
FCC-BCC-ICOS-HCP 1
2
3
4
5
FCC
BCC
ICOS
FCC/HCP
HCP
Designed to study general systems which may contain different structures.
B123 1
2
3
4
BCC
B1
B2
B3
Identifies three ∑5 symmetric tilt boundaries in a BCC bicrystal.

Two-Dimensional Crystals

Filter name Structure Notes
Crystal 1Hexagonal Identifies particles with hexagonal crystal structure in two dimensions.
Crystal + Defects 1
2
Crystal
Defect
Identifies hexagonal crystal and defect particles in two dimensions.
Feedback

VoroTop is under active development. Please be in touch with questions, comments, requests, or suggestions for improvement, or if you are interested in collaborating on research projects.

Related Software

The following software packages can be used in conjunction with VoroTop:

VoroTypes A Python tool that deterministically enumerates all combinatorial types of Voronoi cells for a given crystal structure, producing filter files for use with VoroTop. Reads CIF and POSCAR files.
Voro++ A software library for computing three-dimensional Voronoi tessellations, developed by Chris Rycroft (University of Wisconsin).
OVITO A visualization and analysis software package for atomistic data, developed by Alexander Stukowski.
AtomEye An atomistic configuration viewer, developed by Ju Li (MIT).