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Polarization Workflow

CLI workflow for spatially binned three-folded wurtzite polarization.

Command: get-three-folded-wurtzite-polarization

Calculate spatially binned polarization from three-folded site dipoles.

The workflow first calculates each center's dipole using the three-folded polarity analysis. It then sums those dipoles in a fixed three-dimensional grid and divides by a hull, bounding-box, or simulation-cell bin volume. Optional 2D heatmaps project the selected polarization component onto xy, xz, or yz.

Examples

  1. Bin an AlN slab in x and y using occupied convex-hull volumes:
     reaxkit get-three-folded-wurtzite-polarization --bins-x 20 --bins-y 20 --bins-z 1 --volume-method hull --periodic xy --charge-source formal --formal-charge Al=3 N=-3

  2. Generate per-frame Pz heatmaps with one shared color scale:
     reaxkit get-three-folded-wurtzite-polarization --bins-x 30 --bins-y 30 --heatmaps --heatmap-plane xy --heatmap-component z --global-scaling

  3. Analyze selected frames with cell-normalized bins:
     reaxkit get-three-folded-wurtzite-polarization --frames 0:101:10 --bins-z 20 --volume-method cell

Arguments

Scientific choices

Flag Required Default Help Choices
--center, --cation No Al Choose center species. Example: --center Al Ga, analyzes Al- and Ga-centered sites.
--neighbor, --anion No N Choose neighbor species. Example: --neighbor N, searches nitrogen atoms for basal and apical roles.
--proton No H Choose proton-like species. Example: --proton H, groups sites by nearby hydrogen atoms.
--charge-source No auto Choose dynamic or formal charges. Example: --charge-source formal --formal-charge Al=3 N=-3, calculates charge-weighted values with those charges. auto, reaxff, formal
--formal-charge No Assign species formal charges. Example: --formal-charge Al=3 N=-3 H=1, uses charges in elementary-charge units.
--neighbor-cutoff No 3.0 Set the candidate radius in angstrom. Example: --neighbor-cutoff 2.5, excludes neighbors farther than 2.5 angstrom.
--proton-cutoff No 2.0 Set the proton-proximity radius in angstrom. Example: --proton-cutoff 1.8, marks sites within 1.8 angstrom of H.
--c-axis No 0.0, 0.0, 1.0 Set the Cartesian polar-axis direction. Example: --c-axis 0 0 1, interprets positive z as UP.
--periodic No xyz Choose periodic directions. Example: --periodic xy, wraps candidates across a and b while leaving the surface normal open. none, x, y, z, xy, xz, yz, xyz
--cell-lengths No Override cell lengths in angstrom. Example: --cell-lengths 10 10 16, uses that cell for every frame.
--cell-angles No 90.0, 90.0, 90.0 Set angles for --cell-lengths in degrees. Example: --cell-angles 90 90 120, defines a hexagonal cell.
--frames No Select zero-based source frames. Example: --frames 0:101:10, includes frames 0 through 100 every 10 frames.
--every No 1 Stride the selected frames. Example: --every 5, keeps every fifth selected frame.
--polarity-tolerance No 1e-10 Set the zero-polarity tolerance in angstrom. Example: --polarity-tolerance 1e-6, treats smaller basal means as zero.
--bins-x No 1 Set the number of x-direction bins. Example: --bins-x 20, divides the reference x extent into 20 intervals.
--bins-y No 1 Set the number of y-direction bins. Example: --bins-y 20, divides the reference y extent into 20 intervals.
--bins-z No 1 Set the number of z-direction bins. Example: --bins-z 10, divides the reference z extent into 10 intervals.
--volume-method No hull Choose the bin-volume estimator. Example: --volume-method bbox, uses occupied coordinate extents inside every bin. hull, bbox, cell
--heatmap-plane No xy Choose the heatmap projection plane. Example: --heatmap-plane xz, sums bins along y. xy, xz, yz
--heatmap-component No z Choose the plotted polarization component. Example: --heatmap-component z, colors the map by Pz. x, y, z

Input and file selection

Flag Required Default Help Choices
--engine No Select the input adapter. Example: --engine reaxff, bypasses engine auto-detection. reaxff, ams, lammps
--input No . Set the path used for engine detection. Example: --input ./run, inspects ./run.
--run-dir No . Set the fallback simulation directory. Example: --run-dir ./run, resolves default files there.
--fort7 No fort.7 Select the ReaxFF charge file. Example: --fort7 ./run/fort.7, streams charges from that file.
--fort78 No fort.78 Select the applied-field file. Example: --fort78 ./run/fort.78, reads field samples from that file.
--xmolout No xmolout Select the coordinate trajectory. Example: --xmolout ./run/xmolout, reads atom names and positions there.
--summary No Select optional simulation metadata. Example: --summary ./run/summary.txt, reads timing and cell metadata there.

Outputs and plots

Flag Required Default Help Choices
--heatmaps No False Write one 2D polarization heatmap per frame. Example: --heatmaps, writes PNG files under heatmaps.
--global-scaling, --no-global-scaling No False Share color limits across frames. Example: --global-scaling, makes all frame colors directly comparable; --no-global-scaling rescales each frame.
--figure-dpi No 180 Set heatmap resolution. Example: --figure-dpi 300, writes 300-DPI PNG files.
--output-dir No Choose the CSV and heatmap directory. Example: --output-dir ./polarization, writes artifacts there.
--detail-format No Optional detail format (default: Parquet; legacy: CSV). parquet, csv

Execution

Flag Required Default Help Choices
--execution No auto Execution backend; unsupported backends fall back to serial with a logged reason. auto, serial, threads, processes
--workers No 0 Frame workers: auto or N (default: auto).
--chunk-size No 0 Maximum in-flight frames: auto or N.

Storage and cache

Flag Required Default Help Choices
--run-id No Run identifier for run-scoped layout. Example: --run-id run_91ac0e, which reuses that run identifier.
--project-root No reaxkit_workspace Project root that contains inputs/, data/, analysis/, etc. Example: --project-root ./workspace, which stores run artifacts there.
--analysis-id No Optional analysis artifact id; defaults to run id. Example: --analysis-id comparison-a, which names the analysis artifact explicitly.
--input-cache, --no-input-cache No True Reuse parsed input frames across commands (default: enabled; use --no-input-cache to force source reads for reproducibility checks or benchmarks). Example: --no-input-cache, which reloads frames from their source files.
--frame-cache-max-gb No 10.0 Maximum workspace frame-cache size in GiB (default: 10; use 0 for unlimited). Example: --frame-cache-max-gb 20, which caps cached frames at 20 GiB.
--output-profile No standard Select the shared artifact policy. Standard writes declared default outputs; minimal keeps core tables; full and legacy include optional details. Default: standard. Example: --output-profile full, which includes declared optional detail tables. minimal, standard, full, legacy

Diagnostics and compatibility

Flag Required Default Help Choices
-h, --help No show this help message and exit
--help-all, --all-flags No Show every option, grouped by purpose.
--log No quiet Choose console logging detail. Example: --log verbose, prints diagnostic progress information. verbose, quiet

Common Runtime and Presentation Arguments

These are shared workflow-level CLI flags added before command-specific options, covering runtime context (engine/input/storage) and output presentation/export behavior.

Each command table above includes its shared and inherited options.